Solve (3x+6)/4 - (2x-6)/5 = (x+7)/8.

To solve this equation for x, we need to get x on its own. To do this, we first need to multiply through by the denominators of the fractions, as none of them contain an x term. Multiplying through by 8 first, we get 2(3x+6) - 8(2x-6)/5 = x+7. We then need to multiply through by 5 to get 10(3x+6) - 8(2x-6) = 5(x+7). Now there are no fractions. The next thing to do is to expan the brackets. We have 10(3x) + 10(6) - 8(2x) - 8(-6) = 5(x) + 5(7) which is the same as 30x + 60 - 16x + 48 = 5x + 35. We can now rearrange the equation to get x terms on the left, and constants on the right. 30x - 16x - 5x = 35 - 60 - 48 and we then simplify this to get 9x = -73. Finally, we can solve for x by diving through by 9, the coefficeint of x, to get x = -73/9 = -8 1/9.

Answered by Laura T. Maths tutor

16883 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

i) It is given that f(x)=(-5-33x)/((1+x)(1+5x)), express f(x) in the form A/(1+x) + B/(1+5x) where A,B are integers. ii) hence express the integral of f(x) between x=3 and x=0 in the form (p/q)ln4 where p,q are integers.


If y = exp(x^2), find dy/dx


What does it mean for a function to have one to one mapping?


Calculate the integral of e^x*sin x


We're here to help

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