Length in units:
Use phytogoras theorem or measure it by a ruler if your using a graph paper
AB = 5.65 units
AC = 5.83 units
CB = 1.41 units
Perimeter =5.65 + 5.83 + 1.41 = 12.89 units
Area = 1/2 * 1.41 * 5.65 = 3.98units
2² - y - 5 = 0
Evaluate the power.
4 - y - 5 = 0
Calculate the sum or difference.
-1 - y = 0
Move constant to the right side and change its sign.
-y = 1
Change the signs on both sides of the equation.
y = -1
Sixteen million three hundred thousand