Solve algebraically the simultaneous equations 3x + 2y = 15 and 2x + 4y = 10

Firstly, we need to eliminate on of the terms of the equation, either the x or the y term, by combining the two equations into one equation. To do this we can add or subtract the two equations from each other to make one term disappear: For example if we times the first equation by 2 it becomes 6x + 4y = 30. We can then subtract the second equation from this new equation: 6x + 4y = 30 minus 2x + 4y = 10. This equals 4x = 20. Solve to find x, x = 20/4 = 5.We can now use this x value to find what y equals by substituting the x value into one of the equations.For example 3(5) + 2y = 15 which simplifies to 15 + 2y = 15 so y = 0.

EB

Related Maths GCSE answers

All answers ▸

What is a vector?


How do you solve an equation with brackets?


Jill and four friends go camping together for 5 days. The friends share the cost of the trip equally. These costs are: £120 for fuel, £58 for food, £100 for equipment and £207 for activities. How much does Jill have to pay for her share of the costs?


Solve 5x – 3 > 3x + 11