Answer:
y = 120x
Step-by-step explanation:
y=mx + b is what we need where m is the slope and b is the y-intercept.
the train travels at about 120km/hour, thus the slope is 120.
y= 120x +b. to find the y intercept plug in any coordinate.
240 = 120(2) +b. you find that the y-intercept is 0.
final equation: y= 120x
Number 19 you are comparing one measurement to another. Since it says 1/2 inch equals 4 ft, we want to find out how many more inches are needed if the given scale was 2/3 = 4 ft. Now lets find a common denominator for both scales stated in inches. We have 2/3 inch and 1/2 inch. Our denominator are the bottom parts of the fraction where we need to find a common factor for the denominator so we can add or subtract fractions. We have a 3 and a 2. You may always use the multiplication between two denominators to find a common factor such as 3 times 2 which equals 6 for both denominators. Now we multiplied the 3 by 2 to get 6 so the top part (numerator needs to be multiplied the the 2 because we changed the bottom part by 2 as well. You should notice that when you reduce your fraction now 4/6 is 2/3. Just a self check example there. As for 1/2 we multiplied a 3 to get 6 for the denominator so we need to multiply the numerator by 3 as well. You now should have 4/6 and 3/6. Since the question asks for how many more inches we need to subtract 4/6 from 3/6 and we get 1/6 inch for our answer.
Answer:
∠RST = 120°
Step-by-step explanation:
We assume the positions of the lines and angles will match the attached figure. The angle addition theorem gives a relation that can be solved for x, then for the value of angle RST.
∠RSU +∠UST = ∠RST
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78° + (3x -12)° = (6x +12)° . . . . . substitute given values into the above
54 = 3x . . . . . . . . . . . . . . . . divide by °, subtract 3x+12
108 = 6x . . . . . . . . . . . multiply by 2
120° = (6x +12)° = ∠RST . . . . add 12, show units
The measure of angle RST is 120 degrees.
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<em>Additional comment</em>
Note that we don't actually need to know the value of x (18) in this problem. We only need to know the value of 6x.
For the 11 the first one is x = 4y and for the 2 one it will be x=−6−2y
Using the tangent rule:
Tangent(angle) = Opposite leg / Adjacent leg
We will use the 23 degree angle to solve for x.
Tangent(23) = X / 6
x = 6 * tangent(23)
x = 2.5
