Question

4v^2 + 8v + 5 = 10 What would I add to this equation to create a perfect square?

Answer 1

Answer:

v₁ = 2.5; v₂ = 0.5.

Step-by-step explanation:

4v² + 8v + 5 = 10

4v² + 8v + 5 - 10 = 10 - 10

4v² + 8v - 5 = 0

D = 8² - 4 · 4 · (-5) = 64 + 80 = 144

$v_{1} =\dfrac{-8-\sqrt{144} }{2 \cdot 4} =\dfrac{-8-12 }{8} =\dfrac{-20}{8} =-2.5\\\\v_{2} =\dfrac{-8+\sqrt{144} }{2 \cdot 4} =\dfrac{-8+12 }{8} =\dfrac{4}{8} =0.5$