The answer for that problem is z =12+6
Answer:
Nina practiced the viola for 11.25 hours last week.
Step-by-step explanation:
Juan practiced the violin for 9 hours last week. For each 3 hours that he practices the violin, he practices 2.5 hours of cello. So
3h violin - 2.5h cello
9h violin - xh cello


He practiced 7.5 hours of cello, the same as Nina.
For every 3 hours Nina spends practicing the viola she practices the cello for 2 hours. So:
3h viola - 2h cello
xh viola - 7.5h cello



Nina practiced the viola for 11.25 hours last week.
Answer:
C
Step-by-step explanation:
x²+2x-15 = x²-3x+5x-15 = x(x-3)+5(x-3)=(x+5)(x-3)
or delta:
∆=2²-4*1*(-15)=4+60=64
√∆=8
x1 = (-2+8)/2 = 3
x2=(-2-8)/2=-5
and 4x+20 = 4(x+5)
The same is (x+5), so it is GCF. answer C
Answer:
12,400
Step-by-step explanation:
so what you are going to first is 400 times 31 which is 12,400
Answer:
x = 6
Step-by-step explanation:
using Pythagoras' identity in the right triangle.
the square on the hypotenuse is equal to the sum of the squares on the other 2 sides , that is
x² + (x + 2)² = 10² ← expand parenthesis on left side and simplify
x² + x² + 4x + 4 = 100 ( subtract 100 from both sides )
2x² + 4x - 96 = 0 ( divide through by 2 )
x² + 2x - 48 = 0
(x + 8)(x - 6) = 0 ← in factored form
equate each factor to zero and solve for x
x + 8 = 0 ⇒ x = - 8
x - 6 = 0 ⇒ x = 6
however, x > 0 , then x = 6