Solve these simultaneous equations algebraically: y=2x^2 - 7x + 4 & y=4x-1

As we have two equations of x for y we can make these equal to each other. This gives the following:2x2 - 7x + 4 = 4x - 1As with any quadratic we want to make it equal to 0. This gives the following:2x2 - 7x + 4 - 4x + 1 = 0Simplifying this gives:2x2 - 11x + 5 = 0We know want to find two numbers that multiply together to give 5 and when multiplied by 2x and 1x respectively give -11x.There are only two numbers that can give 5 which is 5 and 1. In order to get -11x we need to multiply the 5 by 2x.As the resultant 11x is negative and the 5 positive both 5 and 1 must be negative. This gives the following:(2x-1)(x-5)=0To solve, make each bracket =0.2x-1 = 0 and x-5 = 0x = 1/2 and x = 5Now we have the x values all that needs to be done is to calculate the respective y value. Choose the simplest y equation from the question, which is y = 4x - 1.Therefore when:x = 1/2, y = 4(1/2) - 1 or y = 1x = 5, y = 4(5) - 1 or y = 19

NR
Answered by Nathaniel R. Maths tutor

4935 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

The equation of line L is y= 3x+2 and the equation of line M is 3y–9x+5=0. Show that these lines are parallel.


Write x^2+6x+14 in the form of (x+a)^2+b where a and b are constants to be determined.


It is given that sin(x) = 1/2. Find the value of sec(x)


Smartphones are on sale. A smartphone now costs only 80% of its original price. By how many per cent would we need to increase the current price of the smartphone in order to bring it back to the original price?


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