Answer:
ANGLE 2 and ANGLE 3 are Vertically Opposite angles.
x+ y = 96 → y = 96 - x (1)
And the price per plain cake * the number he sold + price of the decorated cake * the number he sold = total sales
So
8x + 12y = 800 (2)
Subbing (1) into (2), we have that
8x + 12 (96 - x) = 800 simplify
8x + 1152 - 12x = 800
-4x + 1152 = 800 subtract 1152 from both sides
-4x = -352 divide both sides by -4
x = 88 = the number of plain cakes he sold
And 96 - x = 96 - 88 = 8 = the number of decorated cakes he sold
The solution of the equation after solve the equation, 2x − 3 4x = 21 is 4. Option 3 is correct.
<h3>How to obtain the solution of equation?</h3>
To obtain the solution of an equation, the similar terms should be arranged together and then mathematical operation need to be performed to simplify it.
The equation which is provided to solve is,

To solve this equation, arrange the like terms as,

Add number 3 both side of the equation as,

Divide both side of the equation with number 6, we get,

Hence, the solution of the equation after solve the equation, 2x − 3 4x = 21 is 4. Option 3 is correct.
Learn more about the solution of the equation here;
brainly.com/question/21283540
Answer:
letter c. 6x-y=16
Step-by-step explanation: