A "triangle" with the angles 0, 90, and 90 degrees cannot be considered a triangle since the two 90 degree angles make a right angle, and 0 degrees would mean a flat line. Rather it would resemble something like a straight U that is stretched sideways.
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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brainly.com/question/2883790
The correct answer to your question is −
-30
m + 35
Hope this helps!
BTW can I have brainliest?