10x3=30 hours
30/4= 7.5 hours to study for each exam
3xy+x=-29
-3xy -3xy
x= -3xy-29
X=the man's age
500-2x=394
-500 -500
-2x=-106
-2x/2=-106/-2
x=53
FINAL ANSWER: 53 years old
Hope this helps! :)
Answer

Step by step explanation
Let the points be A and B
A ( 5 , 1 ) ⇒ ( x₁ , y₁ )
B ( -3 , -5 )⇒ ( x₂ , y₂ )
Now, let's find the distance between theses two points:
Distance = 
Plug the values

Calculate

Evaluate the power

Add the numbers

Write the number in exponential form with a base of 10

Reduce the index of the radical and exponent with 2

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The distance formula is used to determine the distance ( d ) between two points. If the co-ordinates of the two points are ( x₁ , y₁) and ( x₂ , y₂ ) , the distance equals the square root of x₂ - x₁ squared + y₂ - y₁ squared.
Hope I helped!
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