Can someone help me and give me an explanation?

Follow these steps using the algebra tiles to solve the equation −5x + (−2) = −2x + 4. 1. add 5 positive x-tiles to both sides and create zero pairs. 2. add 4 negative unit tiles to both sides and create zero pairs. 3. divide the unit tiles evenly among the x-tiles. x =

Does the point (1, sqrt 7) lie on circle shown.

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c