Question

Can someone help me find u?

Answer 1

`\large\boxed{u=4}`

Explanation:

`s=(1)/(2)(u+v)t\\\\\text{Substitute the values of}\ s,\ v\ \text{and}\ t\ \text{to the equation:}\\\\s=360,\ v=20,\ t=30\\\\(1)/(2)(u+20)(30)=360\qquad\text{multiply both sides by 2}\\\\2\!\!\!\!\diagup^2\cdot(1)/(2\!\!\!\!\diagup_1)(u+20)(30)=2\cdot360\qquad\text{use distributive property}\\\\30u+600=720\qquad\text{subtract 600 from both sides}\\\\30u=120\qquad\text{divide both sides by 30}\\\\u=4`