Question 11

loading...

Prev/Next links

waecmaths question: 

Find the value of y for which the expression $\frac{{{y}^{2}}-9y+18}{{{y}^{2}}+4y-21}$is undefined.

Option A: 

6, –7

Option B: 

3, – 6

Option C: 

3, –7

Option D: 

–3, –7

waecmaths solution: 

$\begin{align}  & \text{For the expression}\frac{{{y}^{2}}-9y+18}{{{y}^{2}}+4y-21}\text{ to undefined }{{y}^{2}}+4y-21=0 \\ & {{y}^{2}}+4y-21=0 \\ & (y+7)(y-3)=0 \\ & y=-7,\text{ }y=3 \\\end{align}$

maths year: 
maths topics: