Answer:
a = 4
Step-by-step explanation:
Ez, I did it where 6a - 3a which is just 3a and added the 21 to the other side. So now it is 12 = 3a which is simply 4.
When you cube something you times that number by itself 3 times.
Answer:
-15
Step-by-step explanation:
15+(-15)=15-15+0
Average reading score is given by the expression,
y = 0.153x + 255.4
Here, x in the number of years past 1970.
To find the year in which the average reading score is 259.378, substitute the value of 'y' in the given expression.
y = 0.153x + 255.4
259.378 = 0.153(x) + 255.4
0.153x = 259.378 - 255.4
0.153x = 3.978
x = 
x = 26
That means given average reading score 259.378 will be 26 years after 1970.
Therefore, 1996 is the year in which the average reading score will be 259.378.
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