Suppose you are a solving a quadratic equation using the quadratic formula andSuppose you are a solving a quadratic equation using the quadratic formula and this is your work so far:
2x2+7x−15=0
x=
−7 ±72−42−15
22
x=
−7 ±???
4👈
What number goes in place of ???
this is your work so far:
In the numerator of the quadratic formula, after simplifying, becomes -7 ± √49 + 120 / 4. So the number that goes in place of ??? is √169, which simplifies to 13.
Therefore, the correct expression is:
x = -7 ± 13 / 4.