1- Choice C is correct
The correct answer is (x – 6) Factor each trinomial x2 − 9 x + 18 and x2 – 7 x + 6 x2 − 9 x + 18⇒(x – 6) (x − 3) x2 – 7 x + 6⇒(x – 1) (x – 6)
|
2- Choice A is correct
The correct answer is 18 cm2 a=6⇒ area of triangle is =12 (6× 6)=362 =18 cm2
|
3- Choice D is correct
The correct answer is 62 degrees 46∘ + 72∘=118∘ 180∘ – 118∘=62∘ The value of the third angle is 62∘ .
|
4- Choice B is correct
The correct answer is x≥ 10.5 Simplify: 15 – 43 x ≤ 1 ⇒ – 43 x ≤ – 14 ⇒ – x ≤ – 10.5 ⇒x≥ 10.5
|
5- Choice A is correct
The correct answer is 12 1 + 2 b2 b2 = 1b2⇒(b≠0) b2 + 2 b3 = 2 b2 ⇒ 2 b3 − b2 = 0 ⇒ b2 (2 b − 1) = 0 ⇒ 2 b − 1 = 0 ⇒ b =12
|
6- Choice D is correct
The correct answer is 52 765 × 745=765 + 45=7105=72
|
7- Choice B is correct
The correct answer is b If a7 + c7 = c7 + b7 then: a7 = b7 ⇒ a = b
|
8- Choice D is correct
The correct answer is 178.48 Underline the hundredths place: 178.47_86 Look to the right if it is 7 or above, give it a shove. Then, round up to 178.48
|
9- Choice A is correct
The correct answer is (1,2) y = 6 x – 1 A.(1,2)⇒2 = 6 – 1⇒2 ≠ 5 B.(– 2, – 13)⇒ – 13 = – 12 – 1⇒ – 13 = – 13 C.(3,17)⇒ 17 = 18 – 1⇒17=17 D.(1,5)⇒5 = 6 – 1⇒ 5 = 5
|
10- Choice D is correct
The correct answer is 126 210 × 60100 = 126
|
11- Choice B is correct
The correct answer is 35 a + b + c=64 a + b + c + d4 = 28 ⇒ a + b + c + d = 112 ⇒ 64 + d = 112 d = 112 – 64 = 48
|
12- Choice A is correct
The correct answer is y=1 − x Solve for each equation: (2,3) A.y = 1 – x ⇒ 3 = 1 – 3 ⇒ 3≠− 2 B.y =3 ⇒3=3 C.x=2 ⇒2=2 D.y=x + 1⇒3=2 + 1 ⇒ 3 = 3
|
13- Choice B is correct
The correct answer is 298 If a = 9 then : 3 a2 + 7 a − 8⇒3 (9)2 + 7 (9) − 8⇒3 (81) + 63 − 8=298
|
14- Choice D is correct
The correct answer is $3,536 32 × $115 = $3680 Payable amount is: $7216 − $3680 = $3536
|
15- Choice C is correct
The correct answer is q6 (q3) . q3) = q3 + 3 = q6
|
16- Choice A is correct
The correct answer is 8 x2 – 64 = 0 ⇒ x2 = 64 ⇒ x = 8
|
17- Choice C is correct
The correct answer is x2 − 4 x − 12 Use FOIL (First, Out, In, Last) (x + 2) (x − 6) = x2 − 6 x + 2 x − 12=x2 − 4 x − 12
|
18- Choice B is correct
The correct answer is 72 549 = 183=6 , 729 = 243=8 , 369 = 183=4 , 459 = 153=5 72 is prime number
|
19- Choice A is correct
The correct answer is 7.5 If 7.5 < x ≤ 11.0, then x cannot be equal to 7.5
|
20- Choice C is correct
The correct answer is 16 If a= 8 , then: b= 623 + 4 ⇒ b= 363 + 4 ⇒ b= 12 + 4 = 16
|
21- Choice D is correct
The correct answer is 37 sinB= (the length of the side that is opposite that angle)(the length of the longest side of the triangle) = 37
|
22- Choice A is correct
The correct answer is 825 Set of number that are not composite between 1 and 50 : A= 1,2,3,5,7,11,13,17,19,23,29,31,37,41,43,47 n(A)= 16 ⇒p= 1650 = 825
|
23- Choice B is correct
The correct answer is $22,000 loss c(2) = (2)2 + 6 (2) + 12 = 4 + 12 + 12=28 3 × 2=6⇒6 − 28= − 22 ⇒ $22,000 loss
|
24- Choice A is correct
The correct answer is y=59 x + 169 − 9 y=− 5 x − 16 ⇒ y=− 5− 9 x − 16− 9 ⇒ y=59 x + 169
|
25- Choice C is correct
The correct answer is ln (32) − 4 ex + 4=32⇒ln (ex + 4)= ln (32) (x + 4) ln (e)=ln (32) x + 4=ln (32) ⇒ x = ln (32) − 4
|
26- Choice B is correct
The correct answer is 1517 tan θ = 815 ⇒ we have following triangle, then c = √82 + 152 = √64 + 225 = √289 = 17 cos θ = 1517
|
27- Choice D is correct
The correct answer is: M = 3 + A A = J – 5
|
28- Choice D is correct
The correct answer is 2 METHOD ONE: log2(x + 6) – log2(x − 2)=1 Add log2(x − 2) to both sides: log2(x + 6) – log2(x − 2)+log2(x − 2)=1+log2(x − 2) And simplify: log2(x + 6)=1+log2(x − 2) Logarithm rule: a = logbba ⇒ 1 =log221 = log22 then: log2(x + 6)=log22 + log2(x − 2) Logarithm rule: logca+logcb=logca b then: log22 + log2(x − 2) = log22 (x − 2)⇒log2(x + 6) = log22 (x − 2) When the logs have the same base: logb(f(x)) = logb(g(x)) ⇒ f(x) = g(x) x + 6 = 2 (x − 2) ⇒ x + 6 = 2 x – 4 ⇒ − x = − 10 ⇒ x = 10 METHOD TWO We know that: logab − logac = logabc and logab = c ⇒ b = ac Then: log2(x + 6) − log2(x − 2)=log2x + 6x − 2 = 1⇒ x + 6x − 2=21=2⇒x + 6 = 2 (x − 2) ⇒ x + 6=2 x − 4⇒2 x − x = 6 + 4 ⇒ x = 10
|
29- Choice B is correct
The correct answer is 21 C94 = 9!4!(9 − 3)! = 9!4! 6! = 9 × 8 × 7 × 6!4! × 6! = 9 × 8 × 74 × 3 × 2 × 1 = 21
|
30- Choice D is correct
The correct answer is x ≥ 6 The number under the square root symbol must be zero or greater than zero therefore: x − 6 ≥ 0 ⇒ x ≥ 6 domain of function = [6, + ∞)
|
31- Choice B is correct
The correct answer is (2,2) {12 x + 4 y=326 x − 2 y=8⇒ Multiplication (– 2) in first equation {12 x + 4 y=32− 12 x + 4 y=− 16 Add two equations together ⇒8 y=16 ⇒ y=2 then: x=2
|
32- Choice C is correct
The correct answer is 74 f(x)=4 x − 12⇒ y=4 x − 12 ⇒ 2 y = 4 x – 1 ⇒ 2 y + 1 = 4 x ⇒ 2 y + 14 = x f − 1=2 y + 14 ⇒ f − 1(3) = 74
|
33- Choice A is correct
The correct answer is – x2 – 6 x + 4 (g + f)(x) = g(x) + f(x) = (– x2 – 3 – 5 x) + (7 − x) – x2 + 4 – 5 x – x = – x2 – 6 x + 4
|
34- Choice D is correct
The correct answer is (4,− 7), 3 √2 (x – h)2 + (y – k)2 = r2 ⇒ center: (h,k) and radius:r (x – 4)2 + (y + 7)2 = 18 ⇒ center: (4,− 7) and radius: 3 √2
|
35- Choice A is correct
The correct answer is 4 x + y = 4 If two lines are parallel with each other, then the slope of the two lines is the same. Then in line y = 4 x , the slope is equal to 4 And in the line 4 x + y = 4 ⇒y = 4 x − 4 the slope equal to 4
|
36- Choice C is correct
The correct answer is − 30 ≤ x ≤ 18 | 6 + x |8 ≤ 3 ⇒ | 6 + x | ≤ 24 ⇒ − 24 ≤ 6 + x ≤ 24 ⇒ − 24 − 6 ≤ x ≤ 24 − 6 ⇒ − 30 ≤ x ≤ 18
|
37- Choice B is correct
The correct answer is 513 + i 1413 If z1 = x1 + i y1 and z2 = x2 + i y2 ⇒ z1z2 = x1 x2 + y1 y2x22 + y22 + i x2 y1 − x1 y2x22 + y22 In this problem: x1 = 4, x2 =2, y1 = 1, y2 =− 3 4 + i2 − 3 i = 513 + i 1413
|
38- Choice D is correct
The correct answer is √3 tan (π3) =√3
|
39- Choice B is correct
The correct answer is 2 a2 √3 a √48 a7 b2√2 a2 b2=4 a2 b√32 a b = 2 a2 √3 a
|
40- Choice B is correct
The correct answer is 4 (2 x + 1) f(x)=x − 48 ⇒ y = x − 48 ⇒ 8 y = x – 4 ⇒ 8 y + 4 = x f − 1 = 8 x + 4 = 4 (2 x + 1)
|