Answer:
18
Step-by-step explanation:
30*0.4=12
This means 40% of 30 is 12 and Ana has completed 12 problems.
30-12 = 18, so she still needs to do 18 problems.
Answer:
The answer is 10y + 48.
Step-by-step explanation:
First you have to get rid of brackets by expanding :

Next you have to collect like-terms :

The number could be anything because whatever it is it can be quadrupled
A(–2, 4), B(4, 4), C(4, –2), D(–2, –2)
-> select some diagonal: AC
midpoint is at A+(1/2)*AC
-> calculate vector AC:
AC=(4-(-2),-2-4)=(6,-6)
-> calculate half length of AC:
(1/2)*AC=(3,-3)
A+(1/2)*AC=
(-2,4)+(3,-3)=(1,1) which is the midpoint
so the first option is correct