Answer:
101 cm (to 3 sf)
Explanation:
-First you want to find side CD:
. Draw a line from point C directly down to make a right angled triangle (you can lable the extra point whatever letter you want but for this explanation it's gonna be x)
. You know that CX will be 16.7cm because its the same length as BA
. To find CD you need to use SOH,more specifically the hypotenuse using SOH
. H=O/S (O=16.7, S= sin(43))
.put this in your calculator and you'll get CD=24.4868624 (don't round yet)
-now you wanna find AD but more specifically XD because that's the little part you don't know:
. Using the same triangle from earlier, we use CAH now to find A (aka XD)
. A=C*H (C=cos(43), H=24.4868624 (the value of H/CD from the previous calculation)
. That should give you: 17.90855746
. You're still not done, do 17.90855746+21.2=39.10855746 (this is your value for AD
-add all your values now:
39.10855746+24.4868624+16.7+21.2=101.4954199
-now round to 3 significant figures:
101.4954199 -> 101cm
The perimeter is 101cm