Answer:
x1 = 4
x2 = -5
Step-by-step explanation:
There is a formula to solve the quadratic equations, which is:
[-b +- √ (b² - 4 ac) ] / (2a)
Quadractic equations have this look:
ax² + bx + c = 0
You need to stablish the numbers:
where a, is the number with x², b the x and c, the independent term.
x² + x - 20 = 0 For this case:
a = 1 ; b = 1 ; c = -20. We replace in the formula
[-1 +- √ (1² - 4 1 (-20)) ] / (2 .1)
(-1 + √81) / 2 = 4
(-1 - √81) / 2 = -5
