The variable is x.
Hope that helps :)
Answer:
Formula
A = 1/2 b * h
Substitute
Area = 60 in^2
b = x
h = 2x - 1
60= 1/2 * x * (2x - 1)
Solve
60 = 1/2 * x (2x - 1) Multiply by 2
60 * 2 = x(2x - 1)
120 = x (2x - 1) Remove the brackets.
120 = 2x^2 - x Subtract 120 from both sides.
2x^2 - x - 120 = 0 This factors.
(2x + 15)(x - 8) = 0
Solve for x
2x + 15 = 0
2x = - 15
x = -15/2
x = - 7.5 a negative measurement is useless. Discard this answer.
x - 8 = 0
x = 8
Area (Check)
base = 8
height = 16 - 1 = 15
Area = 1/2 * 8 * 15 = 60 as it should
Answer
Use Area = 1/2 * b * h to find the base and the height.Step-by-step explanation:
Use the equation to find the slope: m=y2-y1/x2-x1 and plug in each of the y coordinates into the numerator and each of the x coordinates in the denominator
m=-2-3/4-8
-5/-4
m=5/4
Plug in the slope and one of the ordered pairs into y=mx+b. I’ll use (8,3)
3=5/4(8)+b
3=10+b
-7=b
Equation: y=5/4x-7
It's 21 square units. If you map it on a complex plane (x-axis is real numbers, y-axis is imaginary numbers) you'll see that the sides of the rectangle is 3 and 7 which multiply to 21.