A = 1/2h(b + B)
2A = h(b + B)
h = 2A/(b + B)
Let x be the time at 11 mph, and let y be the time at 15 mph.
x + y = 45 ............(1)
Therefore:
y = 45 - x ............(2)
Now we can write the equation for the total calories required:
6x + 9.75y = 300 ........(3)
Plugging the value for y from equation (2) into equation (3), we get:
6x + 9,75(45 - x) = 300 .......(4)
which simplifies to:
-3.75x = -138.75
x = -138.75/-3.75 = 37 minutes.
The answer is 37 minutes at 11 mph and 8 minutes at 15 mph.
Answer:
she can cut 2/20=18 left
Step-by-step explanation:
Answer:
x = - 1
Step-by-step explanation:
Length ( l ) = 2x + 8 cm
Width / Breadth ( b ) = 2 cm
Area ( rectangle ) = 12 cm
Formula : -
Area ( rectangle ) = lb
12 = ( 2x + 8 ) ( 2 )
Divide 2 on both sides,
12 / 2 = ( 2x + 8 ) ( 2 ) / 2
6 = 2x + 8
2x + 8 = 6
2x = 6 - 8
2x = - 2
x = - 2 / 2
x = - 1