Question

Question To BrainlyTeachers :)

Subject:- Mathamatices

Heading :- Simplify the expressions and evaluate them as directed.

(1) x ( x - 3 ) + 2 for 1

(2) 3y ( 2y - 7 ) - 3 ( y - 4 ) - 63 for y = - 2

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Answer 1

Answer:

Ans.1=0

Ans.2=21

Step-by-step explanation:

To simplify the expressions and evaluate them as directed.

(1) x ( x - 3 ) + 2 for 1

Ans. Here we have to find the value of expression for x=1

let

$f(x) = x(x - 3) + 2 \\ \\ for \: x = 1 \\ \\ put \: value \: of \: x \\ f(1) =1(1 - 3) + 2 \\ \\ = 1( - 2) + 2 \\ \\ = - 2 + 2 \\ \\ f(1)= 0$

(2) 3y ( 2y - 7 ) - 3 ( y - 4 ) - 63 for y = - 2

Ans. Let the expression be

$f(y) = 3y(2y - 7) - 3(y - 4) - 63 \\ \\ for \: y = - 2 \\ \\ f( - 2) = 3( - 2)(2( - 2)- 7) - 3( - 2 - 4) - 63 \\ \\ = - 6( - 4 - 7) - 3( - 6) - 63 \\ \\ = - 6 \times ( - 11) + 18 - 63 \\ \\ = 66 + 18 - 63 \\ \\ = 84 - 63 \\ \\ f( - 2)= 21$

Hope it helps you.