Question
Evalute: ${(7.8)^2- (2.2)^2}$
✓
Answer
$(7.8)^2- (2.2)^2$
$= (7.8 + 2.2)(7.8 - 2.2)$
$= 10.00 × 5.6$
$= 56$
$= (7.8 + 2.2)(7.8 - 2.2)$
$= 10.00 × 5.6$
$= 56$
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
If $\text{x}-\frac{1}{\text{x}}=7$ then find the value of $\text{x}^2+\frac{1}{\text{x}^2}$.
→A cycle was sold at a gain of $10\%.$ Had it been sold for $Rs. 260$ more, the gain would have been $14\%.$ Find the cost price of the cycle.
→$\underline{\ \ \ \ \ \text{B}\ \ \text{A} \ \ \text{A}\\\text{+}\ \ \text{B}\ \ \text{A} \ \ \text{A}\ }\\\underline{\ \ \ \ 3\ \ \ \text{A}\ \ \ 8\ }$
→Factorise the following, using the identity $a^2+ 2ab + b^2= (a + b)^2 a^2x^2+ 2ax + 1$
→Find the cube root of $512$ by prime factorisation method.
→Write the greatest common factor in each of the following terms.
$2xy, -y^2, 2x^2y$
→$2xy, -y^2, 2x^2y$
The diagonals of a rhombus are 7.5 cm and 12 cm . Find its area.
Solve: $8x + 3 = 27 + 2x$
→Subtract: $\frac{-5}{6}\ \text{from}\ \frac{1}{3}$
→Find the angle measure $x$ in this figure.
→