Answer: (15) see below (16) 284 (17) option 1 (18) option 3
(19) see below (20) 33 (21) L = 50, w = 10
Explanation:
15) 7xy + 3x + 5
↓ ↓ ↓
↓ ↓ 5 is a term with no variable so is a constant
↓ 3x is a term with a coefficient of 3
7xy is a term with a coefficient of 7
Constant Coefficient Term
7 X
3x X
5 X X
16) 12a² - 3 |b| + 2a ; a = -5, b = -2
12(-5)² - 3 |-2| + 2(-5)
= 12(25) - 3(2) - 10
= 300 - 6 - 10
= 294 - 10
= 284
17) 4(k + 5) = -2(9k - 4)
4k + 20 = -18k + 8 Distributed 4 and -2
22k + 20 = 8 Added 18k to both sides
22k = -12 Subtracted 20 from both sides
k = -12/22 Divided 21 from both sides
k = -6/11 Simplified (GCF = 2)
18) V = π r²h
V/(π r²) = h Divided π r² from both sides
19) v = s² + (1/2)sh
v - s² = (1/2)sh Subtracted s² from both sides
2(v - s²) = sh Multiplied both sides by 2
2(v - s²)/s = h Divided s from both sides
1 2 3
subtract s² X
divide by s X
multiply by 2 X
20) F = (9/5)C + 32 ; F = 91
91 = (9/5)C + 32
59 = (9/5)C Subtracted 32 from both sides
295 = 9C Multiplied both sides by 5
32.8 = C Divided 9 from both sides
33 = C Rounded to the nearest whole number
21) Perimeter (P) = 2Length (L) + 2width (w)
Given: P = 120, L = 5w
P = 2L + 2w
120 = 2(5w) + 2w
120 = 10w + 2w
120 = 12w
10 = w
L = 5w
= 5(10)
= 50