Solve the simultaneous equation: 3x+2y=8 and 2x+5y=-2

3x+2y=8 (1)2x+5y=-2 (2)So you need to have a common multiple of either x or y in this example I’ll equate the x of both equations so I’ll multiply (1) by 2 and (2) by 3 2( 3x+2y=8). 6x+4y=16 (3).3(2x+5y=-2) 6x+15y=-6 (4)Subtract equation (4) by (3) 6x+15y=-6 -(6x+4y=16)0x+11y=-22y=-2 substitute your value of y into either equation (1) or (2) 3x+2y=83x+2(-2)=83x-4=83x=12x=4double check your answers for x and y into equation (2) 2x+5y=-22(4)+5(-2)=-28-10=-2 so x=4 and y=-2

RD

Related Maths GCSE answers

All answers ▸

How do you know whether to use sin, cos or tan to find the angle in a triangle?


What is Pythagorus Theorem ? Find the length of BC if given a right angle triangle ABC where AB is 8cm and the length of the hypotenuse AC is 10cm ?


Solve the equation: x^2 + 9x + 20 = 0


Karen got 32 out of 80 in a maths test. She got 38% in an English test. Karen wants to know if she got a higher percentage in maths or in English. Did Karen get a higher percentage in maths or in English?