Answer: B) Infinitely many solutions; both equations are equivalent
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Work Shown:
x+y = 4 ... start with the first equation
x + (-x+4) = 4 ... replace y with (-x+4)
x-x+4 = 4
0x+4 = 4
0+4 = 4
4 = 4 ... this is a true statement regardless of what x you pick
So there are infinitely many solutions. Each solution (x,y) is of the form (x,-x+4). All solutions fall on the line y = -x+4 which is equivalent to x+y = 4. Note how we add x to both sides.
Or you could start with x+y = 4 and subtract x from both sides to get y = -x+4. Either way, we're dealing with the same equation which is why they both graph out the same line.
P = perimeter = 2L + 2W = 86 cm. Also, L = W + 4. Subst. W + 4 for L,
P = 2(W + 4) + 2W = 86 cm. Then 2W + 8 + 2W = 86 cm, and 4W = 78 cm.
Finally solving for W, W = (78 cm)/4, or 19.5 cm.
If W = 19.5 cm, then L = W + 4 cm = 19.5 cm + 4 cm = 23.5 cm
The rectangle's dimensions are 19.5 cm by 23.5 cm.
Answer:
110 cm^2
Step-by-step explanation:
The first thing that you need to do is find the area of triangle AFE. The area of a triangle is always base*height/2. So in this case, that would be 10*6 divided by 2, which is 30 cm. Next, you will need to know the area of triangle ECB. Using that same formula, you will get 8*10/2, which is 40 cm. Finally, you will need to find the area of the whole rectangle. The area of a rectangle is always the length times the width. In this case, you would have 10*18, which is 180 cm. To get your final answer, you need to subtract the areas of the unshaded area from the whole area. That would be 180-(30+40), which is 110 cm. I hope this helped!
