Best Answer

Mathematical substitution is the process of using one equation to solve for multiple variables. For example:

Equation 1: x + y = 4

Equation 2: 2x + y = 16

Using equation 1, solve for y:

y = 4 - x <-- Plug this into equation 2. This is substitution because you are replacing y in equation 2 with what y is equal to in equation 1.

2x + y = 16 ----> 2x + (4 - x) = 16

Now you can solve for x: x + 4 = 16; x = 12

You can then substitute the value of x back into the equation that is solved for y:

y = 4 - 12; y = -8

Check both equations:

Equation 1: -8 + 12 = 4; 4 = 4 (Correct)

Equation 2: 2(12) + (-8) = 16; 24 - 8 = 16; 16 = 16 (Correct)

We have successfully used substitution to solve for two different variables, x and y.

Q: How do you do math substitution?

Write your answer...

Submit

Still have questions?

Continue Learning about Other Math

yes

By substitution.

Graphing is not necessarily easier than elimination or substitution. If you are good at drawing graphs, and do not like algebra, then graphing is easier. However, elimination and substitution are much faster, and graphing can often get awkward when working with more complicated formulae.

That's exactly the purpose of the substitution method ... to get an equation with one less variable. When you have it, you solve it for the variable that's left.

True. To solve a three variable system of equations you can use a combination of the elimination and substitution methods.

Related questions

you don't.

yes

yes, because obviously you know how

Which property is demonstrated below? If t=s then s=t

Do you mean 4th? because it is impossible to figure out 4xtxh without a solution, an even then, it is impossible without substitution.

When you check an answer by using it in another sum e.g2x+7=13x=3substitute to second-4x+6=18x=3 which is correct

idk im trying to figure it out myself..... lol jk gtg im doing homework.... =(

substitution menthod

Substitution

marginal rate of substitution

I can give you several sentences.Use that ingredient as a substitution for the one you don't have.He is going in as a substitution for the quarterback.This is a substitution for the real thing.Margarine could be used as a substitution.

Substitution - song - was created in 2009.