Slope and Standard Form questions ???

Question

1. Find the x and y intercepts of the line given the equation: 7x+2y=-21

2. Write the equation 2y=12-5x in standard form.

Answer 1

1. write the equation in slope-intercept form y =mx + b. m = slope and b is y-intercept.

7x+2y=-21

Subtract 7x from each side.

7x+2y-7x=-7x-21

Divide each side by 2.

y = -7/2x -21/2

y-intercepts is -21/2.

x-intercept is where the line crosses the x-axis, so y = 0

x-intercept = -21/7=-3

2. standard form line equation is Ax + By = C.

2y=12-5x

Add 5x to each side.

5x+2y = 12.

Comments

The intercept form of a line equation is x/a + y/b = 1, where, a is x - intercept,  and b is y - intercept.

1). The equation is 7x + 2y = - 21.

Write the equation in intercept - form.

7x/(- 21) + 2y/(- 21) = 1

x/(- 21/7) + y/(- 21/2) = 1

x/( - 3) + y/(- 21/2) = 1.

Compare the above equation with, intercept form of a line equation.

x - intercept is - 3, and y - intercept is - 21/2.