Question

3x + 4y = 24
4x-3y = 7 substitution method​

Answer 1

Step-by-step explanation:

3x + 4y = 24 --------- (equation i)

4x - 3y = 7 ----------(equation ii)

From equation (i) :-

-> 3x = 24 - 4y

-> x = ( 24 - 4y) ÷ 3

Putting the value of x in equation (ii) :-

-> 4 { ( 24 - 4y ) ÷ 3 } - 3y = 7

-> [ ( 96 - 16y ) /3 ] - 3y / 1 = 7

Multiply 3 to -3y /1 to make it's denominator equal to 3 .

-> ( 96 - 16y - 9y ) / 3 = 7

-> ( 96 - 25y ) / 3 = 7

-> 96 - 25y = 7 × 3

-> -25y = 21 - 96

-> -25y = - 75

-> 25y = 75

-> y = 75 / 25

-> y = 3

Now, we can find the value of x also.

-> x = { 24 - 4(3) } ÷ 3

-> x = { 24 - 12 } ÷ 3

-> x = 12 / 3

-> x = 4

Answer 2

Answer

Step-by-step explanation:

3x+4y=24   1

4x-3y=7       2

using 1

3x+4y=24

4y=24-3x

y=24-3x      this question is wrong