Question

Solve the equation 7y+4 by y+2=-4y+8

Answer 1

Step-by-step explanation:

y+2=-4y+8

5y=6

y=6/5

substituting the value of y in the first equation

7(6/5)+4

=42/5 +4

=8.4+4

=12.4

Answer 2

QUESTION:

$\frac{7y + 4}{y + 2} = - 4y + 8$

ANSWER:

We do the cross multiplication first;

$7y + 4 = ( - 4y + 8)(y + 2)$

solving RHS side;

$7y + 4 = y( - 4y + 8) + 2( - 4y + 8) \\ 7y + 4 = - 4 {y}^{2} + 8y - 8y + 16 \\ 7y + 4 = - 4 {y}^{2} + 16 \\ 4 {y}^{2} + 7y + 4 - 16 = 0 \\ 4 {y}^{2} + 7y - 12 = 0$

factorised it;

we have to split the middle term in such a way that it's sum equal to b i.e 7 and product will be a ×c that is 48

$4 {y}^{2} + 12y - 4y - 12 = 0 \\ 4y(y + 3) - 4(y + 3) \\ (4y - 4)(y + 3)$

So;

$4y - 4 = 0 \\ 4y = 4 \\ y = 1$

or

$y + 3 = 0 \\ y = - 3$

FINAL ANSWER;

$\huge\red{y = 1 \: or \: - 3}$

plz Mark as brainliest