Question 21

loading...

Prev/Next links

waecmaths question: 

Solve for y in the equations

$2x-3y=22$

$3x+2y=7$

Option A: 

–5 

Option B: 

–4

Option C: 

4

Option D: 

5

waecmaths solution: 

$\begin{align}  & 2x-3y=22---(i) \\ & 3x+2y=7---(ii) \\ & \text{Multiply }(i)\text{ by }2 \\ & 4x-6y=44---(iii) \\ & \text{Multiply }(ii)\text{ by }3 \\ & 9x+6y=21---(iv) \\ & \text{Add (iii) and (iv) together} \\ & 13x=65 \\ & x=5 \\ & \text{Substitude }x=5\text{ into }(i) \\ & 2(5)-3y=22 \\ & 10-3y=22 \\ & -3y=12 \\ & y=-4 \\\end{align}$

maths year: 
maths topics: