9514 1404 393
Answer:
x = -7, x = 9
Step-by-step explanation:
We presume your equation is ...
x² -2x -63 = 0
Factors of -63 that have a sum of -2 are -9 and +7. Then the factored equation is ...
(x -9)(x +7) = 0
Solutions make the factors zero.
x -9 = 0 ⇒ x = 9
x +7 = 0 ⇒ x = -7
The solutions to the quadratic equation are x = -7 and x = 9.
<h3>
Answer: A) Dashed line, shaded below</h3>
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Explanation:
2x + 4y < 16 solves to y < -0.5x+4 when you isolate y. The inequality sign does not change direction because we divided both sides by a positive value (in this case, 4).
The graph of y < -0.5x+4 will be the same as the graph of 2x+4y < 16
To graph y < -0.5x+4, we graph y = -0.5x+4 which is a straight line that goes through the two points (0,4) and (2, 3). This is the boundary line of the inequality shaded region. The boundary line is a dashed line because we are not including points on the boundary that are part of the solution set. We only include these boundary points if the inequality sign has "or equal to".
We then shade below the dashed boundary line to indicate points below the boundary line. The shading is done downward due to the "less than" sign.
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Perhaps another method to find what direction we shade is we can try out a point like (0,0). The point cannot be on the boundary line.
Plug those coordinates into either equation. I'll pick the second equation
y < -0.5x+4
0 < -0.5*0+4
0 < 0+4
0 < 4
The last inequality is true, so the first inequality is also true when (x,y) = (0,0). Therefore, the point (0,0) is in the shaded region. The point (0,0) is below the boundary line y = -0.5x+4
So this is another way to see that the shaded region is below the boundary line.
47% of them were bacteria, which means 53% of them were not bacteria.
47+53=100 or 100-47=53
I hope this helps :)
Answer:
x = 24
Step-by-step explanation:
x - (3 · 4) = 12
x - 12 = 12
+ 12 + 12
x = 24
The perimeter of a rectangle is twice the sum of length and width, so the sum of length and width is half the perimeter, 10 3/4 ft.
The width will be the difference between this and the length, hence 5 1/2 ft.
The area is the product of length and width.
A = length×width
A = (5.25 ft)×(5.5 ft) = 28.875 ft²
The area of the sandbox is 28 7/8 ft².