Answer:
base = 28 inches ad height = 9 inches
Step-by-step explanation:
The area (A) of a triangle is calculated as
A = [tex]\frac{1}{2}[/tex]bh ( b is the base and h the height )
Let height = h then b = 2h + 10 = 2(h + 5) and A = 126, thus
[tex]\frac{1}{2}[/tex] 2(h + 5) × h = 126, that is
h(h + 5) = 126 ← distribute left side
h² + 5h = 126 ( subtract 126 from both sides )
h² + 5h - 126 = 0 ← in standard form
(h + 14)(h - 9) = 0 ← in factored form
Equate each factor to zero and solve for h
h + 14 = 0 ⇒ h = - 14
h - 9 = 0 ⇒ h = 9
However, h > 0 thus h = 9
height = 9 inches and base = (2 × 9) + 10 = 18 + 10 = 28 inches