Equation of a Straight Line

Question 1

What are the two forms of equations of a straight line?

Answer 1

• Slope intercept
• Point slope

Question 2

How are both forms written?

Answer 2

Slope Intercept - y = mx + c
Point Slope - y - y1=m(x - x1)

Question 3

What two things must you know out of 4 things in order to solve an equation of a straight line in either form?

Answer 3

1. One Point
2. Two Points
3. The Gradient
4. The y intercept

Question 4

If you are given 1 point and a slope - which form would be most appropriate?

Answer 4

Point slope form

Question 5

What is the gradient of a horizontal line?

Answer 5

0

Question 6

What is the gradient of a vertical line?

Answer 6

Undefined

Question 7

Why is the gradient of a vertical line what it is?

Answer 7

Because the gradient of a line is y2-y1 over x2-x1 and x values of a vertical line are always the same so the denominator cannot be 0 as 0 in the denominator is undefined

Question 8

What is the equation of a vertical line?

Answer 8

x = (whatever the value of x is)

Question 9

What is the equation of a horizontal line?

Answer 9

y = (whatever the value of y is)

Question 10

Which form of equation is always the same?

Answer 10

Slope Intercept Form

Question 11

How do you graph a linear equation?

Answer 11

1. Put in slop intercept/point slope form
2. Plot y axis
3. Use the slope in fractional format (a/b) to go up or down a times or left or right b times to plot the subsequent points

Question 12

How do you find the x intercept

Answer 12

Set the equation to 0 when it is in slope intercept form