Answer:
36 years
Step-by-step explanation:
Let
x = Elga's age
Alvin's age = x + 7
Sum of their ages = 79
Sum of their ages = Alvin's age + Elga's age
79 = (x + 7) + x
79 = x + 7 + x
79 = 2x + 7
79 - 7 = 2x
72 = 2x
x = 72/2
x = 36
Elga's age = x = 36 years
Alvin's age = x + 7
= 36 + 7
= 43 years
Answer:

Step-by-step explanation:
we know that
The total vertical distance (total miles North) traveled is equal to

Remember that


substitute


16x + 64
Hope this helps:)
Answer:4
Step-by-step explanation: each quarter of an hour is 1.5 miles they both can go into 12 so if you multiply 2*4 and 3*4 you get 8/12 and if you multiply 3*3 and 4*3 you get 9/12 then you subtract 9/12 by 8/12 to get so 1/12=1/2 miles so you would subtract 4 1/2 by 1/2 to get 4
Ok to find dy/dx of x+2y=xy we take derivative of both sides with respect to x
1+2dy/dx = x*dy/dx +y*dx/dx
1+ 2dy/dx = x*dy/dx + y* 1
2dy/dx +1 = x*dy/dx + y
2y’ + 1 = xy’ + y
2y’ + 1 - xy’ = y
2y’ -xy’ = y - 1
y’(2-x) = y - 1
so we get finally
y’= (y-1)/(2-x)
Hope this helps you understand the concept! Any questions please ask! Thank you so much!!