<h3>
Answer: Second graph</h3>
Why? Because we draw a dashed line through x = -1/2 = -0.5 on the horizontal number line (aka x axis). Then we shade to the right of this dashed line. The shaded region represents all points that make the inequality true. For example, the point (0,0) is in the shaded region. It has an x coordinate of x = 0 which is larger than -1/2
Side note: the dashed line says "points on this boundary do not count as solutions". So any point with an x coordinate of -1/2 does not count.
Answer:
405 cm²/s
Step-by-step explanation:
The dimensions are increasing at the rate of 3 cm/s, so the dimensions in cm can be described as a function of time by ...
3 + 3t
and
6 + 3t
Then the area is the product of these, or ...
A = (3 +3t)(6 +3t)
A = 9t² +27t +18
and the rate of change of area is given by its derivative with respect to t:
A' = 18t +27
When t=21, the value of this is ...
A'(21) = 18·21 +27 = 405 . . . . cm²/s
Always remember that percent means "out of 100". That means the 40%=40/100=.4
so 40% of 120 is equivalent to .4(120)=48
Hope I helped