Answer:
- 11 or - 15
Step-by-step explanation:
Factorise
x² - 13x + 42
Consider the factors of the constant term (+ 42) which sum to give the coefficient of the x- term (- 13)
The factors are - 6 and - 7, since
- 6 × - 7 = + 42 and - 6 - 7 = - 13, thus
x² - 13x + 42 = (x - 6)(x - 7)
compare to (x + A)(x + B)
A = - 6, B = - 7
thus 3A - B = 3(- 6) - (- 7) = - 18 + 7 = - 11
The factors may also be expressed as (x - 7)(x - 6)
with A = - 7 and B = - 6, then
3A - B = 3(- 7) - (- 6) = - 21 + 6 = - 15
The height of the building is 5.33m.
<h3>How to calculate the height?</h3>
The question is to calculate the height of the building.
Based on the information given, the height will be:
Madeline eye height/Distance from X = Height of building/Building distance from X
1.55/2.75 = x/9.45
x = (1.55 × 9.45)/2.75
x = 5.33 m
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Answer:
<h3>
![23\sqrt[1]{2}](https://tex.z-dn.net/?f=23%5Csqrt%5B1%5D%7B2%7D)
</h3>
Step-by-step explanation:
Simplify.
The equation of the line is y=-2x+3.