Answer:
60.2 m
Step-by-step explanation:
Let x represent the width of the river. The distance from the point across from the tree to the second point is 15 m. The angle from this point to the tree across the river is 76°.
This makes the side opposite the angle x, the width of the river. It also means the 15 m side is adjacent to this angle.
The ratio opposite/adjacent is the ratio for tangent; this gives us the equation
x/15 = tan(76)
Multiply both sides by 15:
15(x/15) = 15(tan(76))
x = 15(tan(76)) ≈ 60.2
The numbers are: 36 and 11 .
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Explanation:
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Let us represent the TWO (2) numbers with the variables;
"x" and "y" .
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x + y = 47 .
y − x = 25.
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Since: " y − x = 25 " ;
Solve for "y" in terms of "x" ;
y − x = 25 ;
Add "x" to each side of the equation:
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y − x + x = 25 + x ;
to get:
y = 25 + x .
Now, since:
x + y = 47 ;
Plug in "(25 + x)" as a substitution for "y"; to solve for "x" :
x + (25 + x) = 47 ;
x + 25 + x + 47 ;
2x + 25 = 47 ;
Subtract "25" from each side of the equation:
2x + 25 − 25 = 47 − 25 ;
2x = 22 ;
Divide EACH SIDE of the equation by "2" ;
to isolate "x" on one side of the equation; and to solve for "x" ;
2x / 2 = 22 / 2 ;
x = 11 ;
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x + y = 47<span> ;
</span>Plug in "11" for "x" into the equation ; to solve for "y" ;
11 + y = 47 ;
Subtract "11" from EACH SIDE of the equation;
to isolate "y" on one side of the equation; and to solve for "y" ;
11 + y − 11 = 47 − 11 ;
y = 36 .
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So: x = 11 , y = 36 ;
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Let us check our work:
y − x = 25 ;
36 − 11 =? 25 ? Yes!
x + y = 47 ;
36 + 11 =? 47 ? Yes!
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The numbers are: 36 and 11 .
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