ABCD is a rhombus on a graph. B(7,10). AC: y=7-4x. Find an equation for DB in the form tx+py+r=0 where t,p&r are integers.

AC and DB must be perpendicular therefore m1m2 = -1. (we can work out the gradient of DB)-4m2 = -1 -----> m2 = 1/4The equation of a line is y-y1=m(x-x1) (sub in x, y and gradient values)y - 7 = 1/4(x-10) (multiply by 4 to get rid of fractions)4y - 28 = x -10 (make = to 0)x - 4y + 18 = 0

AL

Related Maths GCSE answers

All answers ▸

Factorise a^2 - 5a – 14.


How do you solve quadratic inequalities?


Factorise x²+5x+6.


Issy goes to buy some fruit. She has been told by one friend that 2 apples and 3 bananas costs £3.80. She has been told by another friend that 5 apples and a banana costs £3.65. what are the individual costs of an apple and a banana?