MCQ
What is the value of $(3a + 4b) (a - b)$
- A$3a^2 - ab - 4b^2$
- ✓$3a^2 + ab - 4b^2$
- C$(3a^2 + 4b^2)$
- D$(3a^2 - 4b^2)$
✓
Answer
Correct option: B.
$3a^2 + ab - 4b^2$
B. $3a^2 + ab - 4b^2$
Solution:
$(3a + 4b) (a - b)$
$\Rightarrow 3a(a - b) + 4b (a - b)$
$\Rightarrow 3a^2 - 3ab + 4ab - 4b^2$
$\Rightarrow 3a^2 + ab - 4b^2$
Solution:
$(3a + 4b) (a - b)$
$\Rightarrow 3a(a - b) + 4b (a - b)$
$\Rightarrow 3a^2 - 3ab + 4ab - 4b^2$
$\Rightarrow 3a^2 + ab - 4b^2$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
$\left\{\left(\frac{1}{3}\right)^{-3}-\left(\frac{1}{2}\right)^{-3}\right\} \div\left(\frac{1}{4}\right)^{-3}=?$
→Refer the given graph and answer the following question: How many more push-ups are needed to be done on Thursday so that 1t equals the number of push-ups on Wednesday? 
The coefficient of $xy$ $2z$ in $-7x 2y 3z$ is:
→The angle sum of a convex polygon with number of sides $10$ is:
→The following graph shows the temperature forecast $\&$ the actual temperature for each day of a week. On the basis of the graph, answer the following questions.
On which days was the forecast temperature the same as the actual temperature?
→On which days was the forecast temperature the same as the actual temperature?
Total number of outcomes, when a ball is drawn from a bag which contains $3$ red, $5$ black and $4$ blue balls is:
→Tick the correct answer in the following: A man can do a piece of work in $5$ days. He and his son working together can finish it in $3$ days. In how many days can the son do it alone$?$
→A car is traveling at a speed of $54\ km/$ hour, covers a distance in $2.5$ hours. At a speed of $45\ km/hr$, it covers the same distance in
→If one member of a Pythagorean triplet is 2m, then other two members are
The common factors of $10a, 20b$ and $30c$ are:
→