<h3>3
Answers: Choice D, Choice E, Choice F</h3>
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Explanation:
The inequality 6x - 10y ≥ 9 solves to y ≤ (3/5)x - 9/10 when you isolate y.
Graph the line y = (3/5)x - 9/10 and make this a solid line. The boundary line is solid due to the "or equal to" as part of the inequality sign. We shade below the boundary line because of the "less than" after we isolated for y.
Now graph all of the points given as I've done so in the diagram below. The points in the blue shaded region, or on the boundary line, are part of the solution set. Those points are D, E and F.
We can verify this algebraically. For instance, if we weren't sure point E was a solution or not, we would plug the coordinates into the inequality to get...
6x - 10y ≥ 9
6(5) - 10(2) ≥ 9 .... plug in (x,y) = (5,2)
30 - 20 ≥ 9
10 ≥ 9 ... this is a true statement
Since we end up with a true statement, this verifies point E is one of the solutions. I'll let you check points D and F.
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I'll show an example of something that doesn't work. Let's pick on point A.
We'll plug in (x,y) = (-1,1)
6x - 10y ≥ 9
6(-1) - 10(1) ≥ 9
-6 - 10 ≥ 9
-16 ≥ 9
The last inequality is false because -16 is smaller than 9. So this shows point A is not a solution. Choices B and C are non-solutions for similar reasons.
X² - 8x - 20 factors to give option
B) (x - 10)(x + 2)
x² + 8x - 20 factors to give option
A) (x - 2)(x + 10)
x² - x - 20 factors to give option C) (x - 5)(x + 4)
and x² - 9x - 20 is option D) Prime.
I hope this helps!
Answer:
x= -4
Step-by-step explanation:
Simplifying
5x + -4 = 7x + 4
Solving
-4 + 5x = 4 + 7x
Move all terms containing x to the left, all other terms to the right.
Add '-7x' to each side of the equation.
-4 + 5x + -7x = 4 + 7x + -7x
Combine like terms: 5x + -7x = -2x
-4 + -2x = 4 + 7x + -7x
Combine like terms: 7x + -7x = 0
-4 + -2x = 4 + 0
-4 + -2x = 4
Add '4' to each side of the equation.
-4 + 4 + -2x = 4 + 4
Combine like terms: -4 + 4 = 0
0 + -2x = 4 + 4
-2x = 4 + 4
Combine like terms: 4 + 4 = 8
-2x = 8
Divide each side by '-2'.
x = -4
Simplifying
x = -4
Answer:
C
Step-by-step explanation:
If we were to draw a horizontal line from the bottom of the ladder to the bottom of the tree and then draw a vertical line from the bottom of the tree to the top of the ladder, we'd get a right triangle with legs as the distance between the bottom of the tree and the bottom of the ladder and the height of the ladder, and the hypotenuse is the length.
Here, we know the hypotenuse is 10 feet and that the bottom of the ladder is 4 feet away from the bottom of the tree, so use the Pythagorean Theorem to find the height:
h = 
≈ 9.2 feet
The answer is C.
Step-by-step explanation:
the probability of A working is 60% or 0.6, so the probability it does not work is 40% or 0.4.
the probability of B working is 90% or 0.9, so the probability it does not work is 10% or 0.1.
plan 1
it is the probabilty that either A works, or (if it is not working) B works.
0.6 + 0.4×0.9 = 0.6 + 0.36 = 0.96
plan 2
either B works, or (if it is not working) A works
0.9 + 0.1×0.6 = 0.9 + 0.06 = 0.96
both plans have the same success probability.
