A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).

You need to find the value of c so solve the first equation in terms of x:

-2c + x = -7
x = -7 + 2c

then substitute the result (-7 - -2c) into the second equation:

-2c - 6(-7 + 2c) = -5
-2c + (-6 x -7) + (-6 x 2c) = -5
-2c + 42 - 12c = -5
-2c - 12c = -5 - 42
-14c = -47
c = \( \frac{-47}{-14} \)
c = 3\(\frac{5}{14}\)

To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(5a)(2ab) + (4a²)(8b)
(5 x 2)(a x a x b) + (4 x 8)(a² x b)
(10)(a¹⁺¹ x b) + (32)(a²b)
10a²b + 32a²b
42a²b

An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:

d° = b° + c°

To find angle c, remember that the sum of the interior angles of a triangle is 180°:

180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 36° - 57° = 87°

So, d° = 57° + 87° = 144°

A shortcut to get this answer is to remember that angles around a line add up to 180°:

a° + d° = 180°
d° = 180° - a°
d° = 180° - 36° = 144°

To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.

4a - 7a = -3a