I NEED HELP Now that you have learned about quadratic formula. Explain how you would solve x^2+4x-21=0x 2 + 4 x − 21 = 0 using the quadratic formula. Please be sure to include math vocabulary in your answer.

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value

d i think

step-by-step explanation: