Solve the following quadratic simultaneous equation: y = x + 4 and y = x^2 + 4x

Y = x + 4y = x2 + 4x(as both are equal to y, they can be equated)So: x2 + 4x = x + 4(Rearrange to make the equation equal 0 - subtract x and 4)x2 + 3x - 4 = 0(factorise)(x + 4)(x - 1) = 0Therefore: x = -4 or x = 1(plug these values back into the original equation to find the corresponding values of y)If x = -4, y = - 4 + 4So y = 0If x = 1, y = 1 + 4So y = 5 This means the solutions to these equations are:x = -4 and y = 0x = 1 and y = 5

JC
Answered by Julius C. Maths tutor

6776 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Prove that the square of an odd number is always one more than a multiple of 4


what is: a) 1/3 +1/4 ? b) 4/6 + 3/12?


A quarter circle represents a piece of land. The length of the straight sides is 100 ft each. If the land is enclosed by a fence, what is closest to the length, in feet, of the fence?


There are 14 boys in a class and 16 girls. The Mean height of the class is 1.6m, the mean of the girls is 1.5m what is the mean height of the boys?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning