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Simplify the expressions and evaluate th...

Simplify the expressions and evaluate them as directed:
(i) `x(x-3)+2` for `x=1`
(ii) `3y(2y-7)-3(y-4)-63` for `y=2`

Text Solution

Verified by Experts

The correct Answer is:
(i) `x(x-3)+2 = x^2-3x+2`
At `x=1, (1)^2-3(1)+2= 1-3+2 = 0`

(ii)`3y(2y-7)-3(y-4)-63 = 6y^2 - 21y -3y+12-63`
`6y^2-24y-51`
At `y=2, 6(2)^2-24(2)-51 = 24-48-51 = -75`
At `y = -2, 6(-2)^2-24(-2)-51 = 24+48-51 = 21`
(i) `x(x-3)+2 = x^2-3x+2`
At `x=1, (1)^2-3(1)+2= 1-3+2 = 0`

(ii)`3y(2y-7)-3(y-4)-63 = 6y^2 - 21y -3y+12-63`
`6y^2-24y-51`
At `y=2, 6(2)^2-24(2)-51 = 24-48-51 = -75`
At `y = -2, 6(-2)^2-24(-2)-51 = 24+48-51 = 21`
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