Solve for x and y using these simultaneous equations: 2x + 3y = 21, y = 2x - 1

Substitute y = 2x - 1 into the first equation.

2x + 3(2x -1) = 21

2x + 6x - 3 = 21

8x = 24

x = 3

Therefore y = 2(3) - 1 = 5

AL

Related Maths 13 Plus answers

All answers ▸

Mike has 4 blue balls, 6 green balls and 10 yellow balls what is the probability that he will pick a yellow ball.


An amount of money is split between three people: A, B, and C. C gets 50%, B get 3/9, a) what share does A get. A has £10 b) how much does B have? C spends 90% of his money c) how much total money is left between A, B and C?


Find the 100th term in the sequence 3, 7, 11, 15...


Show that 3/10 + 2/15= 13/30