Answer:
see explanation
Step-by-step explanation:
Given x varies directly as y then the equation relating them is
x = ky ← k is the constant of variation
To find k use the condition x = 9 when y = 4
k = =
= 2.25
x = 2.25y ← equation of variation
When y = 8, then
x = 2.25 × 8 = 18
Answer:
Step-by-step explanation:
we know that
The formula to calculate the area for a trapezoid is equal to
where
a and b are the parallel bases
h is the height of trapezoid
A is the area
<em>Solve for a</em>
That means ----> isolate the variable a
Multiply by 2 both sides to remove the fraction in the right side
Divide by h both sides
Subtract b both sides
Rewrite