Solve the simultaneous equations: y = x + 6, x^2 + 2y = 9

y = x + 3x2 + 2y = 9We want to make the squared equation have either only x's or only y's, so we substitute y = x + 3 into the equation:x2 + 2(x + 3) = 9We need to take out the brackets, and simplify this equation.x2 + 2x + 6 = 9x2 + 2x - 3 = 0This is now in the form of a quadratic, so we can solve it:x2 + 2x - 3 = 0(x + 3)(x - 1) = 0 so therefore, x = -3, x = 1These answers for the x-values can give us the y-values, if we substitute them into the original equation:When x = -3, y = -3 + 3 y = 0When x = 1 y = 1 + 3 y = 4We can check our answers by substituting them into the original equation:x = -3, y = 0] (3)2 + 2(0) = 9 = CORRECTx = 1, y = 4] (1)2 + 2(4) = 1 + 8 = 9 = CORRECT

Answered by Hayley H. Maths tutor

2666 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Line Q goes through (0,5) and (4,7). Find the equation of Line Q in the form y = mx + c


Sean drives from Manchester to Gretna Green. He drives at an average speed of 50 mph for the first three hours. He then breaks and drives the final 150 miles at 30 mph. Sean thinks his average speed is 40 mph ,is he correct?


There is a quarter circle with radius 8cm, what is the area of the quarter circle. The answer should be given in terms of pi, units are cm^2.


Factorise x^2 - 14x + 49


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences