coordinate geometry

Question 1

Formula of distance

Answer 1

d=√((x2-x1)²+(y2-y1)²)

Question 2

midpoint formula

Answer 2

(x1 + x2) , (y1 + y2)
————- , ————
2 2

Question 3

gradient formula

Answer 3

vertical rise/ horizontal shift
or
y2-y1
———-
x2-x1

Question 4

left to right

Answer 4

+ve gradient

Question 5

right to left

Answer 5

-ve gradient

Question 6

Parallel lines have the same

Answer 6

Gradient

Question 7

The gradient of perpendicular lines can be found by

Answer 7

-ve reciprocal of the known gradient
eg, m= 3/2
perpen, grad = -2/3

Question 8

x intercept occurs when

Answer 8

y=0

Question 9

Y-intercept occurs when

Answer 9

x=0

Question 10

c tells us

Answer 10

Where the line cuts the y axis

Question 11

How to tell if points lie on a line

Answer 11

subst. RHS or x coord. into the eqn and if its equal to the y coord. it lies on the line
Eg. y=2x + 3 does (-4,-5) lie on the line?
y=2x+3
LHS = -5
RHS= 2(-5) + 3 = -7
does not lie on the line

Question 12

eqn of a straight line given the gradient and a point

Answer 12

y-y1= m (x-x1)

Question 13

how to find the point of intersection of two lines given the equations

Answer 13

simultaneous equations

Question 14

equation of a line

Answer 14

y=mx+c

Question 15

Finding the point(s) of intersection of a line and a curve (linear and non-linear equations)

Answer 15

simultaneous equations with quadratics