Solve the simultaneous equations 3x + y = –4 and 3x – 4y = 6

  1. Label first equation as equation 1 and the second as equation 22) Make y the subject of the equation from equation (1); hence: eq 1 : y = -4 -3x3) Substitute the new equation into equation (2) : 3x- 4(-4-3x)=6 --> 3x+12x +16=64) Collect like terms : 15x = -10, so x = -2/3 5) Substitute calculated value of x into any of the original equations to find y, hence y= -2
MI

Related Maths GCSE answers

All answers ▸

Purple paint is made by mixing red paint and blue paint in the ratio 5 : 2 Yan has 30 litres of red paint and 9 litres of blue paint. What is the maximum amount of purple paint he can make?


Paul buys 12 apples and 10 oranges. 12 apples cost £6. The ratio of the cost of one apple: one orange is 2:3. What is the total cost of the apples and oranges?


Write √98+3√8-√200 in the form a√2, where a is an integer


If 4x = 9y, and 2x + 5y = 95. What is the value of y^2 - x?