Page 146 - Math Course 3 (Book 1)

Equations in Different Forms

Write an Equation in Standard Form Write an Equation in Slope-Intercept Form

Example Example

3 4

in standard form.

Write y = x – 5 Write y –5 = (x – 3) in slope-interception form.
4
3
In standard form, the variables are on the left side
of the equation. A, B, and C are all integers. 4
y –5 = (x – 3) Original equation
3
3
4
y = x – 5 Original equation y –5 = (x – 4) Distributive Property
4
3
3 Multiply each side by 4 to
4(y) = 4 x – 5 4
4 eliminate the fraction. y –5 + 5 = x – 4 + 5 Add 5 to each side.
3
4
4y = 3x – 20 Distributive Property y = x – 1 Simplify.
3
Subtract 3x from each
4y – 3x = 3x – 20 – 3x side.
The slope-intercept form of the
4
–3x + 4y = –20 Simplify. Answer equation is y = x + 1.
3
The standard form of the equation
Answer is –3x + 4y = –20 or 3x – 4y = 20.
Your Turn! Write an Equation in Slope-Intercept Form
Write 3x + 2y = 6 in slope-intercept form.

Write an Equation of a Horizontal Line
3
Write the point-slope form of an equation for a A. y = – x + 3
2
horizontal line that passes through (–3, –4). B. y = –3x + 6

A. y + 4 = 0 C. y = –3x + 3
B. y + 3 = 0 D. y = 2x + 3
C. y – 4 = 0
D. x + 3 = 0

Answer Answer

Write an Equation in Standard Form

Write y – 3 = 2(x + 4) in standard form.

A. –2x + y = 5
B. –2x + y = 7
C. –2x + y = 11
D. 2x + y = 11

Answer

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