Question

10) Substitute x = 1 and y = 3 in each expression
and find its value.
(i)
(ii) x - y + 3
(iii) 2x + 3y
(iv) 8x + 2y - 4
(v) 5x - 7y - 2
(vi) - 20x + 4y + 8​

Answer 1

$\huge\tt\colorbox{lightgreen}{AnsweR}$

$x = 1 \: \: \: and \: \: \: \: y = 3$

⭐

$x - y + 3 \\ = 1 - 3 + 3 \\ = 1 - 0 \\ = 1$

⭐

$2x + 3y \\ 2(1) + 3(3) \\ 2 + 9 \\ 11$

⭐

$8x + 2y - 4 \\ 8(1) + 2(3) - 4 \\ 8 + 6 - 4 \\ 8 + 2 \\ 10$

⭐

$5x - 7y - 2 \\ 5(1) - 7(3) - 2 \\ 5 - 21 - 2 \\ 5 - 23 \\ - 18$

⭐

$- 20x + 4y + 8 \\ - 20(1) + 4(3) + 8 \\ - 20 + 12 + 8 \\ - 20 + 20 \\ 0$