Solve the simultaneous equations 3x + y = –4 and 3x – 4y = 6
Rearrange first equation so we can eliminate one variable: y= - 4 -3x We can then plug this into the second equation so we get rid of the y's and just have x's: 3x-4(-3x-4)=6Simplify this: 3x + 12x+16=6 which gives 15x = -10 and then x=-10/15 = -2/3Can plug x back in to any equation to find out y, this gives: y = - 4 -3(-2/3)y= - 4 +2 so y= -2Final answer: x= -2/3 and y= -2
AC
Related Maths GCSE answers
All answers ▸40 students were surveyed: 20 have visited France 15 have visited Spain 10 have visited both France and Spain. Use this information to complete a Venn Diagram
How do I know which trig formula to use in the exam?
if x^2 + 9x + 20 = 0, what are the possible values of x?
Two simultaneous questions are given as 3x+2y = 9, and x-2y = -5. Find the values for x and y