Question

Verify by substitution
Q3 and 4

Answer 1

3+2x =9
3 + 2(3)=9
=9



8-7y =8-7
=1

root of √1=1


root of √9= 3

Answer 2

I
LHS=
$3 + 2x \\ \\ but \: x \: = 3 \\ \\ hence \\ \\ 3 + 2x \\ = 3 + 2 \times 3 \\ = 9$
=RHS

ii
LHS
=
$8 - 7y \\ = 8 - 7 \times 1 \\ = 8 - 7 \\ = 1$
=RHS
Hence verified