Simplifying
30c + -45d
Factor out the Greatest Common Factor (GCF), '15'.
15(2c + -3d)
Final result:
15(2c + -3d)
Original painting was 39 ft²
(1.00-.2)39=39(.8)=31.2 ft²
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1. First, do 12 x 8 to work out the area of the rectangle, which is 96ft.
Then, to work out the area of a circle, you use the equation πr² to help you. You would multiply π by the radius², which is 16. Now you have just worked out the area of a circle, but not a semicircle, so you would have to divide your answer by two to get the area of this, which would be 25.13 (rounded to 2 d.p).
To get the area of the whole shape, you just have to add the two totals together.
25.13 + 96 = 121.13ft.
Remember to put the units there, or you can lose marks.
Try your best with the next questions! I have written the formulas for the other shapes to help you work out the answers.
Area of a square = Multiply sides together.
Area of rectangle = Multiply width by length.
Area of a circle = Multiply π by the radius².
Area of a semicircle = Multiply π by the radius², and the divide by two.
Area of a triangle = Multiply the base by the height, and then divide by two.
Really hope this helps!
Im pretty sure it would be 10??? if you are putting it as a subtraction problem if not i would try wording it more clearly
