Question

$15.7^2=?$

• A. 246.49
• B. 256.47
• C. 247.49
• D. 156.79

Answer 1

Answer:

A. 246.49

$(a+b)^2=a^2+2ab+b^2$

$15.7^2=(15+0.7)^2$

$=15^2+2\times15\times0.7+0.7^2$

$=225+21+0.49$

$=246.49$