Answer:
a = -5/3
Step-by-step explanation:
3/a × -4 = 20
3a × -4/-4 = 20/-4
3a = -5
a = -5/3
Check:
3/(-5/3) × - 4 = 20
-5 × - 4 = 20
Answer:
90
Step-by-step explanation:
To find s4 we find sum of values when n=1,n=2,n=3,n=4
given expression is 
n=1 , plug in 1 for n

n=2

n=3

n=4

Sum of all 4 terms = 6+12+24+48=90
Answer:
67
Step-by-step explanation:
Since the diagonals in a rectangle are congruent, AC=BD and
7x+18=10x-3
We need to separate x -- to do that, we can first subtract 7x from both sides, resulting in
18=3x-3
Next, add 3 to both sides to get
21=3x
Divide both sides by 3 to get
x=7
Then, we just plug x into 10x-3 to get BD = 7*10-3 = 67
Answer:
3/4 * 2/5
Step-by-step explanation:
Areas is L * W
(1/5 + 1/5) * (1/4 + 1/4 + 1/4) = 2/5 * 3/4
1. 5/6
2. 3/4
3. 2/3
4. 1/6
5. 1/4
6. 1/2