The answer & explanation for this question is given in the attachment below.
Answer:
114
Step-by-step explanation:
Since DE and EF are equal, DEF is an isosceles triangles.
In isosceles triangle, two angles are equal.
So,
∠F = ∠D = 33
Sum of interior angles in a triangles is 180,
∠D + ∠F + ∠E = 180
33 + 33 + ∠E = 180
∠E = 180 - 33 - 33
∠E = 114
Answer:
<h2>
A. ¹²/₅</h2>
Step-by-step explanation:
There is no solution for system of equations: 
if: 
so first, we we need to transform the equations to the form where the coefficients at y will be the same:
Now we have b₁=b₂ and c₁≠c₂ so the system has no solution if a₁=a₂
5k = 12
÷5 ÷5
k = ¹²/₅
Answer:
the first diagram
Step-by-step explanation:
first one
Let's say that in the beginning he weighted x and at the end he weighted x-y, y being the number of kg he wanted to loose.
first month he lost
y/3
then he lost:
(y-y/3)/3
this is
(2/3y)/3=2/9y
explanation: ((y-y/3) is what he still needed to loose: y minus what he lost already
and then he lost
(y-2/9y-1/3y)/3+3 (the +3 is his additional 3 pounts)
(y-2/9y-1/3y)/3-3=(7/9y-3/9y)/3+3=4/27y+3
it's not just y/3 because each month he lost one third of what the needed to loose at the current time, not in totatl
and the weight at the end of the 3 months was still x-y+3, 3 pounds over his goal weight!
so: x -y/3-2/9y-4/27y-3=x-y+3
we can subtract x from both sides:
-y/3-2/9y-4/27y-3=-y+3
add everything up:
-19/27y=-y+6
which means
-19/27y=-y+6
y-6=19/27y
8/27y=6
4/27y=3
y=20.25
so... that's how much he wanted to loose, but he lost 3 less than that, so 23.25
ps. i hope I didn't make a mistake in counting, let me know if i did. In any case you know HOW to solve it now, try to do the calculations yourself to see if they're correct!
