Answer:
39 ft²
Step-by-step explanation:
Area of a triangle = 1/2bh
Let:
base = b = 4 ft
height = h = 3 ft
Solve for the area of the triangle:
A = 1/2(4)(3)
A = 2 * 3
A = 6 ft²
Area of a rectangle = bh
Let:
base = b = 9 ft
height = h = 5 ft
Solve for the area of the rectangle:
A = (9)(5)
A = 9 * 5
A = 45 ft²
Subtract the area of the triangle from the area of the rectangle:
45 - 6 = 39 ft²
39 ft² is your answer.
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18. 5-2x = -4x+9
2x = 4
x = 2
perimeter = length of one side x 3
perimeter = [5-2(2)] x 3
= 3
19. 3(x-1) = 5x-6
3x-3 = 5x-6
-2x = -3
x = 1.5
perimeter = [3(1.5-1)] x 5
=7.5
20. 4/3x-⅓ = x+7
4x-1 = 3x+21 (multiply throughout by 3 to get rid of denominator on LHS)
x = 22
perimeter = (22+7) x 6
= 29 x 6
= 174
^ not sure about qn20 because i can’t tell if it’s x+7 or x divided by 7 it’s kinda blurry
54,54,72
X+X+2X-36=180
4X-36=180
4X= 216
Divide by 4
X= 54
X=54
2(54)-36=72