Finite Math Examples

$y = 4 x - 5$ , $12 x - 3 y = 15$

Step 1

Replace all occurrences of $y$ with $4 x - 5$ in each equation.

Tap for more steps...

Step 1.1

Replace all occurrences of $y$ in $12 x - 3 y = 15$ with $4 x - 5$ .

$12 x - 3 (4 x - 5) = 15$

$y = 4 x - 5$

Step 1.2

Simplify the left side.

Tap for more steps...

Step 1.2.1

Simplify $12 x - 3 (4 x - 5)$ .

Tap for more steps...

Step 1.2.1.1

Simplify each term.

Tap for more steps...

Step 1.2.1.1.1

Apply the distributive property.

$12 x - 3 (4 x) - 3 \cdot - 5 = 15$

$y = 4 x - 5$

Step 1.2.1.1.2

Multiply $4$ by $- 3$ .

$12 x - 12 x - 3 \cdot - 5 = 15$

$y = 4 x - 5$

Step 1.2.1.1.3

Multiply $- 3$ by $- 5$ .

$12 x - 12 x + 15 = 15$

$y = 4 x - 5$

$12 x - 12 x + 15 = 15$

$y = 4 x - 5$

Step 1.2.1.2

Simplify by adding terms.

Tap for more steps...

Step 1.2.1.2.1

Subtract $12 x$ from $12 x$ .

$0 + 15 = 15$

$y = 4 x - 5$

Step 1.2.1.2.2

Add $0$ and $15$ .

$15 = 15$

$y = 4 x - 5$

$15 = 15$

$y = 4 x - 5$

$15 = 15$

$y = 4 x - 5$

$15 = 15$

$y = 4 x - 5$

$15 = 15$

$y = 4 x - 5$

Step 2

Remove any equations from the system that are always true.

$y = 4 x - 5$

Step 3