Question
Factorise : $80-5 a^2$

Answer

$5(4+a)(4-a)$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Solve the equation:
$\frac{x}{7}+\frac{y}{3}=5, \frac{x}{2}-\frac{y}{9}=6$
Show that the quadrilateral formed by joining the midpoints of the pairs of adjacent sides of a rhombus is a rectangle.
Image
In equilateral $\triangle ABC, AD \perp BC$ and $BC = x \ cm.$ Find, in terms of $x,$ the length of $AD.$
By converting to exponential form, find the value of the following :
$\log _3 \frac{1}{9}$
A closed rectangular box is made of wood of $1.5 \ cm$ thickness. The exterior length and breadth are respectively $78 \ cm$ and $19 \ cm,$ and the capacity of the box is $15$ cubic decimeters. Calculate the exterior height of the box.
Prove that: $\sin 60^{\circ} \cdot \cos 30^{\circ}-\sin 60^{\circ} \cdot \sin 30^{\circ}=\frac{1}{2}$
A sheet is 11 cm long and 2 cm wide. Circular pieces 0.5 cm in diameter are cut from it to prepare discs. Calculate the number of discs that can be prepared.
[Hint: Each circular dise will be cut from a square sheet of side 0.5 сm.
$\therefore$ Number of circular discs = Number of square sheets each of side 0.5 сm
$\begin{array}{l}=\frac{\text { Area of given sheet }}{\text { Area of each square sheet }} \\ \left.=\frac{(11 \times 2)}{\left(\frac{1}{2} \times \frac{1}{2}\right)}=(11 \times 8)=88 .\right]\end{array}$
Factorise : $3(2 a-b)^2-19(2 a-b)+28$
In the given figure, ABCD is a rectangle whose diagonals intersect at O. Diagonal AC is produced to E and $\angle ECD =140$. Find the angles of $\triangle OAB$.
Image
If $(a+b)=2$ and $(a-b)=10$, find the values of : $a b$.