Algebraic Manipulation Question. Grade 9?

given a) y= 2x - 5 ...........................(1)

so 2x=y+5

x=(y+5)/2

hence x is in terms of y

b) y= (z + 5)/2

put this equation in eqn(1), we get

2x-5=(z+5)/2

so 2(2x-5)=(z+5)

4x-10=z+5

4x=z+5+10

4x=z+15

x=(z+15)/4

hence solved :-)

y = 2x - 5

1. Adding 5 on both the sides,

y + 5 = 2x - 5 - 5

=> y + 5 = 2x + 0

2. Dividing by 2 on both sides,

(y + 5) / 2 = 2x/2

=> (y + 5) / 2 = x

=> x = (y + 5) / 2 => ANSWER

y = (z + 5)/2

1. Putting y = 2x - 5 from question,

=> 2x - 5 = (z + 5)/2

2. Adding 5 on both sides

=> 2x - 5 + 5 = (z + 5)/2 + 5

=> 2x + 0 = (z + 5)/2 + 5

=> 2x = (z + 5)/2 + 5

3. Dividing by 2 on both sides,

=> 2x/2 = (z + 5)/4 + 5/2

=> x = (z + 5)/4 + 5/2 => ANSWER

x = (y + 5)/2

x = ((z + 5)/2 + 5)/2 = (z + 15)/4

a )

x = ( y + 5 ) / 2

b )

x = [ (z + 5)/2 + 5 ] / 2

x = [ z/2 + 15/2 ] / 2

x = [ z + 15 ] / 4

y = 2x – 5

y + 5 = 2x – 5 + 5

or 2x = (y + 5)

2x ÷ 2 = (y + 5) ÷ 2

x = (y + 5)/2

y = (z + 5)/2

y × 2 = (z + 5)/2 × 2

2y = (z + 5)

y = (z + 5)/2

x = (y + 5)/2

x = [(z + 5)/2 + 2]/2

= [(z + 5 + 10)/2]/2

= (z + 15)/4

------

y = 2x - 5

y = (z + 5)/2

a) 2x = y+5

So x = (y+5)/2

b) 2x - 5 = (z+5)/2

4x - 10 = z+5

4x = z+15

x = (z+15)/4