Solving Linear Equations By Substitution Method.

Hello Everyone.

No doubt the Steemkids Community did more than a good thing for kids like me by introducing the steemit maths Class through our tutor @whileponderin, while in school I fear mathematics and Everytime it mathematics period I get confused cause I know for sure I am going to get whipped by the maths teacher.

It got to a point the sight of the maths teacher scares me as well but the Steemkids community did me well and our tutor is the best so far. I just hope others who fear mathematics like myself are following up on this classes as well.

In today's class we were taught how to solve linear equations using substitution method, the break down from the tutor was superb and with the knowledge I gained I will answering the following questions.

From the instructions above we will be making X the subject of the formula and when we do so we get:

• x=7-y
  We further go ahead and substitute the values of x into the second equation and this would give us: 7-y-y=8
  Collect like terms
  -2y=8-7
  -2y=1
  Divide both sides by -2
  Y=1/-2
  Therefore y=-0.5
  Now we substitute the value of y=-0.5 into the first equation to get the value of x.
  X+(-0.5)=7
  Collect like terms we get:
  X=7+0.5

Therefore x=7.5
Therefore y=-0.5 and x=7.5

From the instructions above we will be solving simultaneously using equation 2 and making y the subject of the formula.

• making y subject of the formula we get: -y=8-x
  Subject of the formula cannot be with a negative sign, so we divide both sides by -1.
  -y/-1=8-x/-1
  Therefore y=-8-x
  We substitute values of y into equation 1.
  X+(-8-x)=7
  Open the bracket.
  X-8-x=7
  Collect like terms
  2x=7+8
  Divide both sides by 2
  X=7.5
  Using equation 2 we substitute values of x=7.5 into x-y=8.
  7.5-y=8
  Collect like terms.
  -y=8-7.5
  Therefore -y=0.5
  To remove the negative sign from the subject of the formula we get
  -y/-1=0.5/-1
  Y=-0.5
  So x=7.5 and y=-0.5.

To confirm if our answers are correct we input the values of x and y into the equation.

X+y=7
Substitute values of x and y we get: 7.5+(-0.5)= 7
7.5-0.5=7

To confirm for equation two we use same method: x-y=8
We substitute values of x and y into the equation
7.5-(-0.5)=8
7.5+0.5=8

With the illustrations above we have been able to confirm that our answers are correct.