Answer:
it is a irrational number
4/d = 2/6
4*6= 2*d
24=2d
d=12
(r-3)/10=r/13
13(r-3)=10r
13r-39=10r
3r=39
r=13
The answer should have been 8.6 that was wrong but it is okay you were close
The range of a function is the set of all possible outputs.
When the quadratic functions are in standard form, they generally look like this:

If a is positive, the function opens up; if it’s negative, the function opens down. In this form, the y-coordinate of the vertex is found by evaluating f(−
). For example, consider this function:
f(x) = 
So we’re gonna do: −b/2a=−8/2(−2)=−8/−4=2
Then, we plug this in:

a is negative, so the range is all real numbers less than or equal to 5.
Learn more about range at
brainly.com/question/2264373
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