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 ▸Solve these simultaneous equations. 5x + 2y = 20 and x + 4y = 13.
how do you solve these simultaneous equations?
There are 10 boys and 20 girls in a class. The class has a test. The mean mark for all the class is 60. The mean mark for the girls is 54. Work out the mean mark for the boys
A bottle contains 300ml of medicine, the dose for a child can be given by (m*a)/150 where m is the child's age in months and a is the adult dosage of 40ml. If you need 2 doses a day, how long will the medicine last until it's empty for a 2y/o child?