Question

Find the gradient of the line 2y = 8x + 1

Find the y-intercept of the line 4y + 8x = -8

Bonus = Does the point (1 ,12) lie on the line y = 3x + 8 ? =

Does the point (-2 ,10) lie on the line y = 14 + 2x

Answer 1

gradient=4 y intersept: B(0;-2) Point (1;12) doesn't lie on y=3x+8

(-2,10) lies on the line y=14+2x

Explanation:

2y=8x+1 => divide both sides by 2=> y=4x+1/2 => gradient = 4

4y+8x= -8 => 4y= -8-8x => y=-2-2x . -2 - I indicated this number with the bold ( this ratio is the y coordinate of y- intersept. x coordinate=0

So the y-intersept is (0;-2)

We have a point (1;12) 1 is x coordinate of the point and 12 is y coordinate.

Put 1 and 12 instead x and y in the given formula. If we get the correct expression => the point lies on the line, if the expression is false=> doesn't lie on the line.

Now lets check !

12=3*1+8

12= 11 - false => the point (1;12) doesn't lie on y=3x+8

Similarly proceed: 10=14+2*(2)

10=14-4

10=10 - right ! Point (-2;10) lies on y=14+2x