Clare buys some shares for $50x. Later, she sells the shares for $(600 + 5x). She makes a profit of x% (a) Show that x^2 + 90x − 1200 = 0

Profit is (New price-Original price)/Original price . As a fraction it is percentage Profit/100. Equate (New price-Original price)/Old Profit to the fraction of Profit in %/100. Cross multiply and come up with a quadratic eqation. 0 (600+5x-50x)/50x=x/100 to give 100(600-45x)=50(x^2) Divide through by 50 2(600-45x)=(x^2) Move all on one side to end up with x^2 + 90x − 1200 = 0

RH
Answered by Raj H. Maths tutor

12177 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the following equation for x: x^2 - 4x - 17 = 4


Solve these simultaneously to find values for a and b: 6a + b = 16 and 5a - 2b = 19


Solve this simultaneous equation: 3x + y = 10, x + y = 4


Find the roots of x^2-9=0


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:

© 2025 by IXL Learning