<span>no está en mi equipo lo siento</span>
To answer this, you need to make a systems of equations.
25x + 35y = 1450
x + y = 50 ----> y = 50 - x
25x + 35(50-x) = 1450
25x + 1750 - 35x = 1450
25x - 35x + 1750 = 1450
-10x + 1750 = 1450
- 1750 -1750
-10x = -300
x = 30
He played tennis for 30min
10 = ax - 3b
First, add 3b to both sides. / Your problem should look like: 10 + 3b = ax.
Second, divide both sides by a. / Your problem should look like:

= x.
Third, switch sides. / Your problem should look like: x =

which is your answer.
The midpoint of two points is the point which divides the line segment joining the two points into two equal parts.
Suppose, we have a line segment AB with a point C, between point A and point B such that the distance AC is equal to the distance CB, then we say that point C is the midpoint of line AB.
Suppose, we have another point D between point A and point C, such that the distance AD is equal to the distance DC, then we say that point D is the midpoint of AC.
Notice that point D is a fourth of line segment AB.
Thus, AD is <span>one fourth the length of segment AB.
Therefore, one fourth the length of a segment can be obtained by evaluating the midpoint of the midpoint of the line segment.
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