Answer:
9
Step-by-step explanation:
Let's first convert this to numbers. When a number is decreased by a certain amount, that is the same as saying that something is subtracted from it. Therefore:
a-7=2
Add 7 to both sides:
a-7+7=2+7
a=9
Hope this helps!
Answer: x=1,y=0
Step-by-step explanation:
X-2y=1.....equation 1
2x-y=2.....equation 2
X=1+2y.......equation 3
Substitute equation 3into 2
2(1+2y)-y=2
2+4y-y=2
2+3y=2
3y=2-2
3y=0
Y=0/3
Y=0
Substitute for y=0 in equation 1
X-2y=1
X-2(0)=1
X-0=1
X=1
X=1 & Y=0
Answer:
z-score for 900 points = -4
Step-by-step explanation:
To find the z scores
z=(x-mean)/standard deviation
so
z=(900-1500)/150
z= -600/150