Question

If -5 is a root of the quadric equation 2x^2 +px-15=0 then:
​a) 3
b) 5
c) 7
d) 1

Answer 1

To find the value of p for which -5 is a root of the quadratic equation 2x^2 + px - 15 = 0, we substitute -5 into the equation and solve for p, which gives us the value of 7.

Step-by-step explanation:

If -5 is a root of the quadratic equation 2x^2 + px - 15 = 0, we can find the value of p by substituting x with -5 in the equation and solving for p.

Substituting x with -5 gives us:

2(-5)^2 + p(-5) - 15 = 0

50 - 5p - 15 = 0

35 - 5p = 0

Now, we can solve for p:

5p = 35

p = 7

Therefore, the value of p that makes -5 a root of the equation is 7.