Question

3x^2-10x=8 which of the values for x make equation true

A.-4
B.-3
C.3
D.4

Answer 1

Answer:

D. 4

Step-by-step explanation:

3x^2-10x=8

3x^2-10x-8=0

Here ,a=3 b=-10 and c=-8.

Then By quadratic formula

x= -b±√b²-4ac÷2a

x=10±√-10²-4(3)(-8)÷2(3)

x=10±√100+96÷6

x=10±√196÷6

x=10±14÷6

Taking + sign

x=10+14÷6

x=24÷6

x=4

Taking - sign

x=10-14÷6

x=-4÷6

x=-2÷3

So the correct answer is 4.