Question

Nick is solving the equation \[3x^2 = 20 - 7x\] with the quadratic formula.

What values should he use for a, b, and c?



A. a = 3
b = 20
c = -7


B. a = 3
b = -7
c = 20


C. a = 3
b = 7
c = -20


D. a = 3
b = -20
c = 7

Answer 1

Okay so we know that the equation for the quadratic formula is x = -b+/- (sqr) b^2 - 4ac.
Well the way to plug the numbers in is by using this equation: Ax^2 + Bx + C = 0 :)
S if you use your equation : 3x^2 = 20 - 7x
First you have to move everything to one side.
So it'll look like this:
3x^2 = 20 - 7x
-20 -20
3x^2 - 20 = -7x
+7x +7x
3x^2 - 20 + 7x = 0
So remember Ax^2 +Bx+ C= 0
3 = A
7 = B
-20 = C
So the answer is C :)

Answer 2

Option C is correct.

a = 3

b = 7

c -20

Explanation:

A quadratic equation is in the form of :

`ax^2+bx+c=0` ....[1]

where a, b and c are coefficient and x is the variable term.

As per the statement:

Nick is solving the equation
`3x^2 = 20 -7x` with the quadratic formula.

Given the equation:

`3x^2 = 20 -7x`

Add 7x to both sides we have;

`3x^2 +7x= 20`

Subtract 20 from both sides we have;

`3x^2 +7x -20=0`

On comparing with equation [1] we have;

a = 3, b = 7 and c = -20

Therefore, the values of a, b and c are:

a = 3

b = 7

c -20