Answer:
C. a = 7
D. c = -3
Step-by-step explanation:
C. 7(2a + 3) + 21 = 100+ 40
14a + 21 + 21 = 140
14a = 140 - 21 - 21
14a = 98
a = 7
D. 6+ 14 - 12c = 56
20 - 12c = 56
-12c = 56 - 20
-12c = 36
c = - 3
I think it is 568 if I’m not mistaken
Answer:
x=27, y=18
Step-by-step explanation:
Angle CB is 128, which means angle AC is 72. We can confirm angle O is also 72, since the lines are straight. Angle AM is 27, because AN is a right angle. 63+72+27= 162 180-162=18 Angle ND is 18.
P = 2(L + W)
L = W + 5
A = 4P + 2
P = 2(W + 5 + W)
P = 2(2W + 5)
P = 4W + 10
A = 4P + 2
A = 4(4W + 10) + 2
A = 16W + 42
A = L * W
A = W(W + 5)
A = W^2 + 5W
W^2 + 5W = 16W + 42
W^2 + 5W - 16W - 42 = 0
W^2 - 11W - 42 = 0
(W + 3)(W - 14) = 0
W - 14 = 0
W = 14 <==
L = W + 5
L = 14 + 5
L = 19 <==
P = 2(19 + 14)
P = 2(33)
P = 66
A = L * W
A = 19 * 14
A = 266
answer : length = 19, width = 14....perimeter = 66....area = 266

Negative multiply negative = Positive
Negative multiply positive = negative

Thus the answer is -4a + 16b - 12c - 12d.