Answer:
C, D, D.
Step-by-step explanation:
Problem 6)
We want to determine the equation of the graphed inequality.
First, let's determine the equation of the line for the inequality. We can see that it passes through the points (-2, 0) and (0, 2). Find the slope:
[tex]\displaystyle m=\frac{\Delta y}{\Delta x}=\frac{2-0}{0-(-2)}=\frac{2}{2}=1[/tex]
So, the slope of the line is one.
And since it passes through the point (0, 2), our y-intercept is two. Therefore, the equation of the line is:
[tex]y=x+2[/tex]
Next, notice that the shaded region is below the line. Also, the line itself is also shaded.
Since the shaded region is below the line, y is less than the graph of the line and since the line itself is shaded, our sign is less than or equal to.
Hence:
[tex]y \leq x + 2[/tex]
Our answer is C.
Problem 7)
We have the inequality:
[tex]-2x+8+5x>2x+1[/tex]
First, solve the inequality. Combine like terms:
[tex]3x+8>2x+1[/tex]
Subtract x from both sides:
[tex]x+8>1[/tex]
And subtract 8 from both sides:
[tex]x>-7[/tex]
Therefore, any value greater than -7 will satisfy the inequality.
Out of the choices, the only choice greater than -7 is -5.
So, our answer is D.
Problem 8)
We have the inequality:
[tex]5x+7\leq 8x-3+2x[/tex]
Again, solve the inequality. Combine like terms:
[tex]5x+7\leq 10x-3[/tex]
Subtract 5x from both sides:
[tex]7\leq 5x-3[/tex]
And add three to both sides:
[tex]10\leq 5x[/tex]
Divide both sides by five:
[tex]2\leq x[/tex]
Flip:
[tex]x\geq 2[/tex]
Therfore, any value greater than or equal to 2 will satisfy the inequality.
Out of the choices, the only choice greater than or equal to 2 is 2.
So, our answer is D.
