Solve the simultaneous equations; 2x + y = 18; x + 3y = 19.
Start by selecting a variable to eliminate from the equations. --> Select x in this case.Take the second equation and multiply by 2. --> 2x + 6y = 38Subtract the first equation from this answer. --> 5y = 20Divide through by 5. --> y = 4Substitute this back into the second equation to solve for x. --> x = 7Substitute both x = 7 and y = 4 into the first equation as a check. --> 2(7) + 4 = 18 --> 14 + 4 = 18. Correct
MA
Related Maths GCSE answers
All answers ▸The difference between two positive numbers is 50. The second number is 50 % smaller than the first one. What are the two numbers?
If x:y = 7:4 and x+y = 88 , work out the value of x–y.
£3000 is invested for 2 years at 3.8% per annum compound interest. What is the total interest earned over the 2 years?
2.5 x 100