My triangle solver says EF ≈ 7.5 ft.
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The law of cosines is usually used for this.
EF^2 = DE^2 +DF^2 -2*DE*DF*cos(D)
.. = 6^2 +11^2 -2*6*11*cos(40°)
.. ≈ 55.88
EF ≈ √55.88 ≈ 7.5 . . . ft
Answer:
13/35
Step-by-step explanation:
13 students choose football.
31 students choose tennis.
this leaves 26 students that chose running.
probability of choosing running is 26/70 = 13/35
Answer: -4x(4x - 15)
Step-by-step explanation:
f(x) = 
+ 60x
y = + 60x
=> - (
- 60x)
=> -4x(4x - 15)
So, you need to do the same operation to each side.
Start out by subtracting 3 from each side
1/4 (20x+8) = -3
Then, multiply both sides by 4
40x+8 = -12
Then, subtract 8 from each side
40x = -20
divide both sides by 40 and you get
x=-1/2
Hope this helped!
Answer:
He set the factored expressions equal to each other. instead of setting them equal to zero
Step-by-step explanation:
f(x) = x^2 + 4x + 3. His work is shown below.
0 = x^2 + 4x + 3
0 = (x + 3)(x + 1)
Here is where we use the zero product property
x+3 = 0 x+1 =0 We do not set them equal to each other
