You question implies simple subtraction is needed:
28-8=20
Answer:
a
Step-by-step explanation: cause
Given that a triangle in the coordinate plane has coordinates of (3, 5), (1, −3), and (−3, 4). Now these points are translated and the new coordinates are (1, 7), (−1, −1), and (−5, 6).
Questioon says to find which type of translation occured from the given choices.
It can be easily found by drawing the given coordinates.
Original position of the triangle is drawn in Brwon colour.
New position of the triangle is drawn in Green colour.
From graph we can clearly see that each of the original coordinate moves two unit left then 2 units upward to get new coordinate.
Hence choice "A) It moved left two units and up two units." is the final answer.
A good place to start is to set
to y. That would mean we are looking for
to be an integer. Clearly,
, because if y were greater the part under the radical would be a negative, making the radical an imaginary number, not an integer. Also note that since
is a radical, it only outputs values from
, which means y is on the closed interval:
.
With that, we don't really have to consider y anymore, since we know the interval that
is on.
Now, we don't even have to find the x values. Note that only 11 perfect squares lie on the interval
, which means there are at most 11 numbers that x can be which make the radical an integer. All of the perfect squares are easily constructed. We can say that if k is an arbitrary integer between 0 and 11 then:

Which is strictly positive so we know for sure that all 11 numbers on the closed interval will yield a valid x that makes the radical an integer.
2x + 5 = 11
(-5)
2x = 6
(/2)
x = 3