A plumber charges £40 for a call out, and an extra £18 for every hour. How long did a job that cost £130 take? The formula for this plumber's charge is: \(T = £60 + £20 \times h\) where \(T\) is the ...

News of a subtle quadratic equation breakthrough has brought algebra forward from the very back of many people’s minds, and algebra is always part of the “when will I ever use this?” rubric people use ...