Question

3. What value should be added to the expression to create a perfect square?

x2 – 10x


5
25
100
–100

Answer 1

have you covered "perfect square trinomials" yet?

Answer 2

Yes @jdoe0001

Answer 3

Rule of thumb of perfect squares is c=(b/2)^2
for the form
ax^2+bx+c

Answer 4

ex. x^2+20x+?
c=(20/2)^2=10^2=100
c=100

Answer 5

\(\bf x^2 - 10x\implies x^2 - (2\cdot 5)x\implies x^2 - 2( 5)x
\\ \quad \\
thus\quad x^2 - 2( 5)x+{\color{red}{ \square }}^2\)

any ideas?