Question

Simplify 3y (2y -7) -3 ( y-4)-63 and evaluate for y =-2

Answer 1

Value obtained by simplifying equation 3y (2y -7) -3 ( y-4)-63 and substituting y = -2  is 21.

Solution:

To simplify the following we first multiply (2y – 7) by 3y and (y – 4) by 3 we get

$6 y^{2}-21 y-3 y-12-63=0$

By simplifying further,

$6 y^{2}-24 y-51=0$

The following after solving becomes a quadratic equation.

Hence the value after solving $6 y^{2}-24 y-51$  

Substituting y = -2 in the equation obtained we get  

$\bold{6(-2)^{2}-24(-2)-51=21}$

Answer 2

Answer:

If y = -2 ,

value of 3y(2y-7)-3(y-4)-63=21

Step-by-step explanation:

Given y = -2 -----(1)

Simplify 3y(2y-7)-3(y-4)-63

=6y²-21y-3y+12-63

=6y²-24y-51----(2)

substitute y=-2 ,we get

Value of 3y(2y-7)-3(y-4)-63

=6y²-24y-51

=6(-2)²-24(-2)-51

=6×4+48-51

=24+48-51

=72-51

=21

Therefore,

If y = -2 ,

value of 3y(2y-7)-3(y-4)-63=21

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