Solve the following simultaneous equations: 3x + 5y = -4 and -2x + 3y = 9
Label the equations 1 and 2 We want to make it so the x are the same number - therefore we have to find a common multiple of 2 and 3 - this is 6 Therefore the equations turn into: 1) 6x + 10y = -8 2) -6x + 9y = 27 Add together: 19y = 19 Therefore y = 1 Plug back into equation 1: 3x + 5 = -4 Therefore x = -3 Check with equation 2: -2(-3) + 3(1) = 9
KP
Related Maths A Level answers
All answers ▸Find an expression in terms of powers of cos(x) for cos(5x)
Find 1 + (1 + (1 + (1 + (1 + ...)^-1)^-1)^-1)^-1
Using answer to previous question state the coordinates of the minimum
An arithmetic progression has a tenth term (a10) = 11.1 and a fiftieth term (a50) = 7.1 Find the first term (a) and the common difference (d). Also find the sum of the first fifty terms (Sn50) of the progression.