To form an equation with the given information, we use the formula :
y = mx + b, m being the slope and b being the y-intercept.
Since it is given that the slope is -9/7, we substitute m with -9/7.
y = -9/7x + b
To find b, we will substitute the known coordinates into the equation :
At point (-7 , 4), x = -7, y = 4
4 = -9/7 (-7) + b
4 = 9 + b
b = 4 - 9
b = -5
Now we know that b = -5, we will substitute b = -5 into the equation that we found earlier, y = -9/7 x + b :
y = - 9/7x - 5
To make it more readable, we can multiply the equation by 7:
7y = -9x - 5
7y + 9x + 5 = 0
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Answer : 7y + 9x + 5 = 0
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Answer:
A) slope = 20.
B) The slope of 20 dollars per hour means that for every hour, the price of the service call increases by 20 dollars (or you could say the price of the service call is 20 dollars every hour, both work.)
Step-by-step explanation:
Recall that slope is y2 - y1 / x2 - x1.
Excellent. We are provided with two points: (1, 60) and (3, 100). Let’s enter this into our formula.
Slope = (100 - 60) / (3 - 1) = 40 / 2 = 20.
Now, to determine what the slope means, we can look at the axis titles on the graph. The x axis title is hours, or time in hours. The y axis title is price of the service call in dollars. Therefore, the slope is price (in dollars) per time (in hours).
This can be restated as: The slope of 20 dollars per hour means that for every hour, the price of the service call increases by 20 dollars (or you could say the price of the service call is 20 dollars every hour, both work.)
Hope this helps!
The numbers are: 36 and 11 .
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Explanation:
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Let us represent the TWO (2) numbers with the variables;
"x" and "y" .
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x + y = 47 .
y − x = 25.
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Since: " y − x = 25 " ;
Solve for "y" in terms of "x" ;
y − x = 25 ;
Add "x" to each side of the equation:
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y − x + x = 25 + x ;
to get:
y = 25 + x .
Now, since:
x + y = 47 ;
Plug in "(25 + x)" as a substitution for "y"; to solve for "x" :
x + (25 + x) = 47 ;
x + 25 + x + 47 ;
2x + 25 = 47 ;
Subtract "25" from each side of the equation:
2x + 25 − 25 = 47 − 25 ;
2x = 22 ;
Divide EACH SIDE of the equation by "2" ;
to isolate "x" on one side of the equation; and to solve for "x" ;
2x / 2 = 22 / 2 ;
x = 11 ;
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x + y = 47<span> ;
</span>Plug in "11" for "x" into the equation ; to solve for "y" ;
11 + y = 47 ;
Subtract "11" from EACH SIDE of the equation;
to isolate "y" on one side of the equation; and to solve for "y" ;
11 + y − 11 = 47 − 11 ;
y = 36 .
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So: x = 11 , y = 36 ;
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Let us check our work:
y − x = 25 ;
36 − 11 =? 25 ? Yes!
x + y = 47 ;
36 + 11 =? 47 ? Yes!
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The numbers are: 36 and 11 .
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4x² + 3x + 5 = 0
x = <u>-3 +/- √(3² - 4(4)(5))</u>
2(4)
x = <u>-3 +/- √(9 - 80)</u>
8
x = <u>-3 +/- √(-71)
</u> 8<u>
</u>x = <u>-3 +/- √(71 × (-1))</u>
8
x = <u>-3 +/- √(71) × √(-1)
</u> 8<u>
</u>x = <u>-3 +/- 8.43i
</u> 8
x = -0.375 +/- 1.05375i
x = -0.375 + 1.05375i x = -0.375 - 1.05375i
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