Check the picture below.
so the picture has a rectangle that is 8 units high and 12 units wide, and it has a couple of "empty" trapezoids, with a height of 5 and "bases" of 9 and 3.
now, if we just take the whole area of the rectangle and then subtract the area of those two trapezoids, what's leftover is the blue area.
Answer:
Let x represents the Sara eat pancake and y represents the Phil eat the pancake.
As per the statement:
Phil ate three less than twice as many pancakes as Sara.
"Twice as many pancake as Sara" means 2x
"three less than twice as many pancakes as Sara" means 2x -3
⇒ .....[1]
It is also given that together they combined to eat 15 pancakes.
⇒ .....[2]
Substitute equation [1] into [2] we get;
Combine like terms;
3x-3 =15
Add 3 to both sides we get;
3x = 18
Divide both sides by 3 we get;
x = 6
Substitute the value of x in [1] we get;
y = 2(6)-3 = 12-3 =9
y = 9
Therefore, the pancakes did each eat are;
Sara eat pancake = 6 and Phil eat pancake = 9