Math review guide

Please help with the problem.

Hi ali, see some quick hints below.

a) you have the height (AB =5) and the length (AF + FD = 10) use these to find the area
b) you have the height of the triangle (AB = 5) and the length of the base (AF = 7) use these to find the area
c) you can use pythogoras to find the length: BD^2 = AB^2 + AD^2
d) the perimeter is the sum of the sides. because it’s a rectangle the length and widths are the same for each side so you can just add up: 2(AB) + 2(AF + FD)

I hope these help

Hi Jack, had a quick ques on part b)… the question asks for the area of the triangle AEF, hence the formula must be [!/2 X AF (base) x EF (height)]. How can we use length of AB in this question?

Hi Anisha, the height is the vertical distance of the triangle. EF could only be the height if it was a right-angled triangle. We aren’t told that it is, so it’s safe to assume that it isn’t.

The only information we have related to the height is the length of AB. We know that the length of AB must be the same as the height of triangle AEF because points A, F and E are all on the edges of the rectangle ABCD.

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