7 im thinking is the answer
Answer: length of DE is about 3.3 ft
Step-by-step explanation: A calculator is necessary!
DE is the unknown hypotenuse of the triangle
get the sine of 23° = 0.3907311285
Use the equation for sine
<em>sin = o/h</em> .
To find h, Substitute values for sin and o. O is EC, Opposite the 23° angle D
<em>0.3907311285 = 1.3/h</em> multiply both sides by h
h(0.3907311285) = 1.3 divide both sides by 0.3907311285
h = 1.3/0.3907311285
3.327096065 = h, the length of the hypotenuse, DE.
Answer:
2 x 10 x 4 + (4 + 10) x 2 x 6 = 80 + 168 = 248
