Answer:
L = 
L = 60.033
Step-by-step explanation:
Answer:
Angle STR = 78°
Step-by-step explanation:
So, since line QS is a straight line, we know that it's 180°. We also know that angles QTR and STR both add up to 180°. That gives us an equation:
20x + 12 + 10x + 33 = 180
Combine like terms
30x + 45 = 180
Subtract 45 from both sides
30x = 135
Divide both sides by 30
x = 4.5
Now we know the value of x. We just need to plug it into angle STR's given value:
10(4.5) + 33 = angle STR
45 + 33 = angle STR
78° = angle STR
a.
The polynomial w^2+18w+84 cannot be factored
The perfect square trinomial is w^2+18w + 81
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The reason the original can't be factored is that solving w^2+18w+84=0 leads to no real solutions. Use the quadratic formula to see this. The graph of y = x^2+18x+84 shows there are no x intercepts. A solution and an x intercept are basically the same. The x intercept visually represents the solution.
w^2+18w+81 factors to (w+9)^2 which is the same as (w+9)(w+9). We can note that w^2+18w+81 is in the form a^2+2ab+b^2 with a = w and b = 9
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b.
The polynomial y^2-10y+23 cannot be factored
The perfect square trinomial is y^2-10y + 25
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Using the quadratic formula, y^2-10y+23 = 0 has no rational solutions. The two irrational solutions mean that we can't factor over the rationals. Put another way, there are no two whole numbers such that they multiply to 23 and add to -10 at the same time.
If we want to complete the square for y^2-10y, we take half of the -10 to get -5, then square this to get 25. Therefore, y^2-10y+25 is a perfect square and it factors to (y-5)^2 or (y-5)(y-5)
Answer:
Option A. x = 8
Step-by-step explanation:
Please see attached photo.
From the attached photo,
we shall determine the value of y. This can be obtained by using pythagoras theory as illustrated below:
(√80)² = 8² + y²
80 = 64 + y²
Collect like terms
80 – 64 = y²
16 = y²
Take the square root of both side
y = √16
y = 4
Finally, we shall determine the value of x. This can be obtained as follow:
From the attached photo,
x = 2y
but:
y = 4
Therefore,
x = 2y
x = 2 × 4
x = 8
50 miles / 4 hours = 12.5 miles per hour
Answer: 12.5
