Descending order for a polynomial means from highest value of exponent to the lowest value of exponent.
If you observe the options you can see that polynomial shown in option A is only listed in descending order i.e. starting from a maximum exponent of x and then moving towards lower exponents of x.
So answer to this question is option A
Answer:
Multiply x + y = 3 by 3 and add it to -3x - 2y = -7
Step-by-step explanation:
When using elimination to solve a system of equations, you multiply one equation by some number. The reason for doing this is that when you add it to the second equation, you want one variable to cancel out. When one variable cancels out (in this case x), you can solve for the other variable (in this case y). I will show this:
3(x + y = 3) = 3x + 3y = 9
3x + 3y = 9
+ -3x + -2y = -7
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y = 2
Now, knowing that y = 2, you can substitute y=2 into either equation to solve for x.
-3x - 2(2) = -7
-3x -4 = -7
-3x = -3
x = 1 | to double check (1, 2) as your answer plug these values into both equations
Finding this solution would not have been possible if not for cancelling out the x's above. The other three are wrong because none of the other options cancels out one of the variables.
Distance = rate x time
D = 450 mph x 2.5 h
D = 1,125 miles
Answer: B. y = 1/2x - 1
Explanation:
I know someone else already answered, but I wanted to explain why the answer is B.
Consider an equation of a line in slope-intercept form: y = mx + b
Since the line intersects the y-axis at -1, that’s the y intercept, or b. We know the slope of the line is positive because it slopes upward from left to right. From each whole number solution point, the line goes up one and two to the right. Slope, represented by m, is “rise” over “run”, or the change in y over the change in x. This makes the slope 1/2.
I hope this helps.