Question

20x2 + 3x + 5 = 7

Help

Answer 1

3/20, -3/10

Explanation:

Its a quadratic equation, use the quadratic formula. (-b+-
`√(b^2-4ac\\)`)/2a

20x^2+3x-2=0

(-3+-
`√(9+80)`)/40

(-3+-9)/40

So you get 6/40=3/20 and -12/40=-3/10

Answer 2

for 20·x+3x+5=7, x= -38/3

for 20x^2+3x+5=7, x=-2/5, x=1/4

sorry, I don't know if the x after the two is a multiplication symbol, or a variable squared, so I put both answers. I hope this helps.

Explanation:

first variation:

1) multiply:

40+3x+5=7

2) add:

45+3x=7

3) move the 45:

3x=7-45

4) solve:

3x=-38

x=-38/3

second variation:

1) move constant to the left:

20x^2+3x+5-7=0

2) simplify:

20x^2+3x-2+0

3) use the quadratic formula:

a=20, b=3, c=-2

x=-3±√3^2-4×20×(-2)/2×20

4) solve:

x=1/4, x=-2/5