Look at one of the vertices of the heptagon where two squares meet. The angles within the squares are both of measure 90 degrees, so together they make up 180 degrees.
All the angles at one vertex must clearly add up to 360 degrees. If the angles from the squares contribute a total of 180 degrees, then the two remaining angles (the interior angle of the heptagon and the marked angle) must also be supplementary and add to 180 degrees. This means we can treat the marked angles as exterior angles to the corresponding interior angle.
Finally, we know that for any convex polygon, the exterior angles (the angles that supplement the interior angles of the polygon) all add to 360 degrees (recall the exterior angle sum theorem). This means all the marked angles sum to 360 degrees as well, so the answer is B.
13.) A=9cm^2
If the area is l•h, and there are 9 cubic squares, that means that the length of each side on the square is 3cm, each square on it equals 1cm.
14.) V=27cm^3
If the volume is l•w•h, then we find the third power square root of 27, so 3•3=9•3=27, the answer is 3cm for the length, width, and height.
15.) V=4,913cm^3
If volume is l•w•h, then what number when raised to the third power equals 4913? The answer is 17, since 17•17=289•17=4913. So the length is 17cm
16.)V=216cm^3
If volume is l•w•h, then what number when raised to the third power equals 216? The answer is 6, since 6•6=36•6=216.
17.)A=121
Is area is l•w, then what number raised to the second power equals 121? The answer is 11, since 11•11=121. Therefore it WILL NOT fit a car with a length of 13ft.
18.)A=141
If area is l•w, then what number raised to the second power equals 141? The answer is 12, since 11.87•11.87=141 (answer was rounded to nearest whole number) meaning that she will need 12ft of fence to enclose her garden.
Answer: 2.815 kilograms
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Work Shown:
1 layer = 0.5 kg
5 layers = 5*(0.5 kg) = 2.5 kg
icing = 15 g = 15/1000 = 0.015 kg
1 candle = 100 g = 100/1000 = 0.1 kg
3 candles = 3*(0.1 kg) = 0.3 kg
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The five layers combine to 2.5 kg. On top of that we have 0.015 kg of icing, and then finally the three candles add 0.3 kg more weight.
The total weight is therefore: 2.5+0.015+0.3 = 2.815 kilograms
She has 501 more pennies than nickles.
