A = (1/2) b * h
h = b - 5
42 = (1/2) * b * (b - 5)
42 = (1/2) * b^2 - 5b
multiply both sides by 2 to clear the fraction (1/2)
2(42) = 2(1/2) *b^2 - 5b
84 = b^2 -5b
Since this is a quadratic equation, subtract 84 from both sides so that it is set = to zero.
b^2 - 5b - 84 = 0
Now factor.
(b - 12)(b + 5) = 0
b - 12 = 0; b = 12
b + 5 = 0; b = -5
You can't have a negative length so the answer is 12m
To check the answer:
A = (1/2) * 12* 7
A = 42 m^2
The answer would be the first option.
Answer:
9
Step-by-step explanation:
10a+7
<u>10(1/5)</u> + 7
<u>2+7</u>
9
<h3>
Answer:</h3>
unshaded area = 25(4 -π) in^2 ≈ 21.46 in^2
<h3>
Step-by-step explanation:</h3>
Each of the shaded circles has a diameter of (20 in)/4 = 5 in, which also is the width of the enclosing rectangle. Then each circle has a radius of 2.5 in, and an area of ...
A = πr^2 = π(2.5 in)^2 = 6.25π in^2
The four circles together have an area of ...
4A = 4·(6.25π in^2) = 25π in^2
The area of the rectangle is the product of its length and width:
A = LW = (20 in)(5 in) = 100 in^2
Since the circles are shaded, the unshaded area is the difference between the rectangle area and the total area of the four circles:
unshaded area = (100 in^2) - (25π in^2) = 25(4 -π) in^2 ≈ 21.46 in^2
8 ounces, it said it at the end of the question.