Question

Solve the given system by substitution.

Answer 1

s = 2

r = 8

Explanation:

subsitution is were you plug in a systerm into the other problem

since they give you R = 4s you take 4s and plug it in were r is in the other equation (subsitution)

so now you have 4s = 1/2s+7

now you want to solve for s so your going to subtract 1/2s from both sides to cancle out the 1/2s --> 4s - 1/2s = 7 --> 3 and 1/2s = 7

now divide both sides by 3 1/2 to get s alone s = 7/3 and 1/2

s = 2

now we have s we take that and plug it into r = 4s

subsitute S as 2 --> r = 4(2)

r = 8

Answer 2

(2, 8)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Equality Properties

Algebra I

• Solving systems of equations using substitution/elimination

Explanation:

Step 1: Define Systems

r = 4s

r = 1/2s + 7

Step 2: Solve for s

Substitution

1. Substitute in r: 4s = 1/2s + 7
2. Subtract 1/2s on both sides: 7/2s = 7
3. Divide 7/2 on both sides: s = 2

Step 3: Solve for r

1. Define equation: r = 4s
2. Substitute in s: r = 4(2)
3. Multiply: r = 8