Photomath is a good one. So is KhanAcademy, but I don't know if they have an app version of the website.
Since y=y. set the equations equal to each then solve
2x + 1 = -x + 4
+x +x
3x + 1 = 4
-1 -1
3x = 3
/3 /3
x = 1
<span>4p - 5 • (p + 6)
</span>-p - 30 = -1 • (p + 30)<span>
</span>
<span> -p - 30</span>