Answer:
9cm
Step-by-step explanation:
- Since PQST is a rectangle, ∠QST=∠QSR=∠90º. So triangle QSR is a right triangle.
- By the Pythagorean Theorem and that SR=6 and QR=10, we can say that 6^2+b^2=10^2. So, 36+b^2=100. And b^2=64 and b=8. So QS=8.
- Now we know that QS=PT=8.
- By the Pythagorean Theorem and that PR=17 and PT=8, we can say a^2+8^2=17^2. So, a^2+64=289. And a^2=225 and a=15.
- We know that TR=15 and SR=6 and TR-SR=TS, so 15-6=9.
The area formula for rectangles is lxw. To solve, I would divide the figure up into 3 rectangles- top,middle and bottom, then find the areas and add them together.
Top: 4x13=52 cm^2
Middle: 5x8=40 cm^2
Bottom: 21x10=210 cm^2
(5 is the width of the middle piece. You get it from subtracting. 21-8-8=5. 13 is the width of the top piece. 5+8=13)
52+40+210
=302 cm^2
So your answer is 302 square centimetres.
first take the 3 and place it over the negative one in quadrant 2