Answer:
AC=16 units
Step-by-step explanation:
The diagonals of a parallelogram bisect each other. It was given that diagonals AC and BD intersect at point E.
This implies that:
.
We substitute the expression for x, we get:
.
Group similar terms to get:
.
.

AC = 2(12-4x)
AC=2(12-4(1))
AC=2(8)
AC=16
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:
a - a or (a +(-a))
Step-by-step explanation:
A negative plus a positive is always zero if they have the same variable.
Answer:
A
Step-by-step explanation:
Given 2 similar figures with sides in the ratio a : b
Then the ratio of their areas is a² : b²
Hence
ratio of sides = 2 : 9, then
ratio of areas = 2² : 9² = 4 : 81 → A