Question

Janelle was trying to find the distance between (3,7) and (9,6) in the coordinate plane. She knew the formula was D=√(9 - 3)^2 + (6 - 7)^2. So she took the square root and got (9-3)+(6-7)=5. Did she get the correct answer? Explain.

Answer 1

hello :
incorrect answer because :

`\sqrt{ a^(2) + b^(2) } \\eq \sqrt{ a^(2) } + \sqrt{ b^(2)} \\eq a+b`
but :

`\sqrt{ (a+b)^(2) } = a+b`........a+b ≥ 0