Cross multiply and you get:
Write and Graph an Equation in Point-Slope Form
(x1, y1) = (–2, 0)
Point-slope form
Answer:
Write the point-slope form of an equation for a line
that passes through (–2, 0) with slope
Write and Graph an Equation in Point-Slope Form
Answer:
Graph the equation
Plot the point at (–2, 0).
Use the slope to find another point on the line. Draw a line through the two points.
A. A
B. B
C. C
D. D
A. y – 4 = –2(x + 3)
B. y + 3 = –2(x – 4)
C. y – 3 = –2(x – 4)
D. y + 4 = –2(x – 3)
Write the point-slope form of an equation for a line that passes through (4, –3) with slope –2.
In standard form, the variables are on the left side of the equation. A, B, and C are all integers.
Multiply each side by 4 to eliminate the fraction.
Original equation
Distributive Property
Writing an Equation in Standard Form
Writing an Equation in Standard Form
4y – 3x = 3x – 20 – 3x
–3x + 4y = –20
3x – 4y = 20
Answer: The standard form of the equation is 3x – 4y = 20.
Simplify.
Change the coefficient of x to be positive
Subtract 3x from each side.
A. A
B. B
C. C
D. D
A. –2x + y = 5
B. –2x + y = 7
C. 2x - y = -11
D. 2x + y = 11
Write y – 3 = 2(x + 4) in standard form.
Example 3
Writing an Equation in Slope-Intercept Form
Distributive Property
Original equation
Add 5 to each side.
Simplify.
A. A
B. B
C. C
D. D
Write 3x + 2y = 6 in slope-intercept form.
A.
B. y = –3x + 6
C. y = –3x + 3
D. y = 2x + 3
Point-Slope Form and Standard Form
A. GEOMETRY The figure shows trapezoid ABCD with bases AB and CD.
Write an equation in point-slope form for the line containing the side BC.
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Point-Slope Form and Standard Form
Step 1 Find the slope of BC.
Slope formula
(x1, y1) = (4, 3)
(x2, y2) = (6, –2)
Point-Slope Form and Standard Form
Step 2 You can use either point for (x1, y1) in the point-slope form.
Using (4, 3) Using (6, –2)
y – y1 = m(x – x1) y – y1 = m(x – x1)
Point-Slope Form and Standard Form
B. Write an equation in standard form for the same line.
Answer: 5x + 2y = 26
Original equation
Distribute Property
Add 3 to each side.
Multiply each side by 2.
Add 5x to each side.
2y = –5x + 26
5x + 2y = 26
A. A
B. B
C. C
D. D
A. y – 6 = 1(x – 4)
B. y – 1 = 1(x – 3)
C. y + 4 = 1(x + 6)
D. y – 4 = 1(x – 6)
A. The figure shows right triangle ABC. Write the point-slope form of the line containing the hypotenuse AB.
A. A
B. B
C. C
D. D
A. –x + y = 10
B. –x + y = 3
C. –x + y = –2
D. x – y = 2
B. The figure shows right triangle ABC. Write the equation in standard form of the line containing the hypotenuse.