Answer:
hello :
2x² +7x - 15 = 0... a = 2 b = 7 c = - 15
Δ = b² - 4ac = 7² - 4(2)(- 15) = 49 + 120 = 169 = 13²
x1 = (-7 +13)/2 = 3
x2 = (-7 - 13)/2 = - 10
the roots are : 3 , - 10
Answer:
x = - 5, x = [tex]\frac{3}{2}[/tex]
Step-by-step explanation:
Consider the product of the factors of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term.
product = 2 × - 15 = - 30, sum = + 7
The factors are + 10 and - 3
Use these factors to split the middle term
2x² + 10x - 3x - 15 = 0 ( factor first/second and third/fourth terms )
2x(x + 5) - 3(x + 5) = 0 ← factor out (x + 5)
(x + 5)(2x - 3) = 0
equate each factor to zero and solve for x
x + 5 = 0 ⇒ x = - 5
2x - 3 = 0 ⇒ 2x = 3 ⇒ x = [tex]\frac{3}{2}[/tex]
