Straight Lines

Question 1

If a question tells you the gradient and a point, what are the steps to find the equation of the line?

Answer 1

Use the point-gradient formula from the formula booklet.
The y and x stay the same.
The m gets replaced by the number that is the gradient.
The x1 and y1 are replaced with the coordinates from the given point.

Question 2

If a question has something like a point (490,h), [so one of the coordinates is a letter], what are the steps to find out what the letter is?

Answer 2

Plug the x and y coordinates into the equation of the line and solve for the unknown letter. (Use nSolve)

Question 3

When do we use nSolve?

Answer 3

Whenever there is an equation with one unknown letter.

Question 4

Which real-life english key words actually means “gradient” in math language?

Answer 4

rate of change
“per” (so like per hour or per car)

Question 5

What are the steps to find the midpoint if you know both endpoints?

Answer 5

You use the midpoint formula from “prior learning”. BUT you have to calculate the x- and y- coordinates completely separately (so like no comma…do two different calculations.

Question 6

What are the steps to find an endpoint, when they give you one endpoint and a midpoint?

Answer 6

You use the midpoint formula from “prior learning”. BUT you have to make two different equations (one for the xs and one for the ys). Then nsolve for x and y.

Question 7

What are the steps to find a perpendicular bisector?

Answer 7

1) Find the midpoint between the two given sites (using the midpoint formula.
2) Find the gradient that would connect the two sites (using the gradient formula)
3) Write down the perpendicular gradient (which will be the gradient we need).
4) Impliment the x- and y-coordinates from the midpoint, as well as the gradient in the gradient-point form.