2 3/4 = 11/4 <=== written as an improper fraction
Answer:
Step-by-step explanation:
To start calculating, we first need to make some proof.
Firstly, since AB = AC, we know that ΔABC is isosceles, which means that ∠ABC = ∠ACB.
Now, looking only to ΔBDE and ΔCDF, we can see that they are similar, because the two of its angles are congruent:
∠BED=∠CFD
∠DBE=∠DCF
To make it easier to visualize which are the corresponding vertexes, we can draw them like this:
And we need to remember that BC is 24, so:
BD+CD=24
Since the triangles are similar, their corresponding sides have constant ratio, which we can calculate from the corresponding sides DE and CF:
This ratio is the same for the other corresponding sides, so we can apply that for BD and CD:
Thus, the measure of CF is approximately 13, alternative D.
Answer:
81
Step-by-step explanation:
1st History test: 73
2nd History test: 77
3rd History test: 81
4th History test: 85
5th History test: 89
73+77+81+85+89 = 405
405/5 = 81
Speed=distance/time
Speed=7.5/3
Speed=2.5 mph