Use Substitution to solve a + s = 304 and 7a + 2s = 1118

Use the substitution method to solve:

a + s = 304
7a + 2s = 1118

Equation 1 is in the correct format.
Equation 2 is in the correct format.

Rearrange Equation 2 to solve for a:

7a + 2s = 1118

Subtract 2s from both sides to isolate a:

7a + 2s - 2s = 1118 - 2s
7a = 1118 - 2s

Now divide by 7:

7a
7

=

1118 - 2s

7

Revised Equation 2:

a =	1118 - 2s
	7

Plug Revised Equation 2 value into a:

1(a) + s = 304
1 * ((1118 - 2s)/7) + s = 304
((1118 - 2s)/7) + s = 304

Multiply equation 1 through by 7

7 * (((1118 - 2s)/7) + s = 304)
7 * (((1118 - 2s)/7) + s = 304)
1118 - 2s + 7s = 2128

Group like terms:

-2s + 7s = 2128 - 1118
5s = 1010

Divide each side by 5

5s
5

=

1010

5

s =	1010
	5

s = 202

Plug this answer into Equation 1

1a + 1(202) = 304
1a + 202 = 304
1a = 304 - 202
1a = 102

Divide each side by 1

1a
1

=

102

1

a =	102
	1

a = 102

Solve using Gauss Jordan Elimination

What is the Answer?

a = 102 and s = 202

How does the Simultaneous Equations Calculator work?

Free Simultaneous Equations Calculator - Solves a system of simultaneous equations with 2 unknowns using the following 3 methods:
1) Substitution Method (Direct Substitution)
2) Elimination Method
3) Cramers Method or Cramers Rule Pick any 3 of the methods to solve the systems of equations 2 equations 2 unknowns
This calculator has 2 inputs.

What 1 formula is used for the Simultaneous Equations Calculator?

Δ = a * e - b * d

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What 7 concepts are covered in the Simultaneous Equations Calculator?

cramers rule: an explicit formula for the solution of a system of linear equations with as many equations as unknowns
eliminate: to remove, to get rid of or put an end to
equation: a statement declaring two mathematical expressions are equal
simultaneous equations: two or more algebraic equations that share variables
substitute: to put in the place of another. To replace one value with another
unknown: a number or value we do not know
variable: Alphabetic character representing a number

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