A triangle with area 45 square inches has a heightthat is two less than four times the base Find the baseand height of the triangle.

Question

I know that you have too substitute variables but im completely lost.

Answer 1

h = 4b - 2

A = bh/2

 

45 = (b(4b - 2))/2

90 = 4b² - 2b

4b² - 2b - 90 = 0

(2b + 9)(2b - 10) = 0

 

2b + 9 = 0 

2b = -9

b = -9/2

If we were looking for zeroes, this would be an answer, but since we're looking for measurement, we don't use negative numbers.

 

2b - 10 = 0

2b = 10

b = 5

 

4(5) - 2 = 18