Answer:
1) y = 2(x+3)^2 -4
2) x+6/x-4
3) 2x^2 + 6x +20 = 0
Step-by-step explanation:
Let's let the weight of a large box be L, and the weight of a small box be S.
We know that 5 large boxes and 3 small boxes is 120kg, so:
5L + 3S = 120
We also know that 7 large boxes and 9 small boxes is 234kg, so:
7L + 9S = 234
You can multiply the first equation by 3 to get:
15L + 9S = 360
See how now both equations have 9S? We can now subtract one from the other:
(15L+9S) - (7L+9S) = 360-234
8L = 126
L = 15.75
Now sub this value back into an equation:
(5x15.75) + 3S = 120
3S = 41.25
S = 13.75
Double check these values
(7x15.75) + (9x13.75)
= 110.25 + 123.75
=234, which is consistent with above.
So a large box is 15.75kg, and a small box is 13.75kg.
Hope this helped
<h3>
Answer:</h3>
See the attached
<h3>
Step-by-step explanation:</h3>
When you square the binomial (a -b), you get ...
... (a -b)² = a² -2ab +b²
That is, both the a² and b² terms have positive signs, and the middle term is twice the product of the roots of the squared terms.
The last two selections have negative signs on the constant, so cannot be perfect square trinomials.
The first selection has a middle term that is -ab, not -2ab, so it is not a perfect square trinomial, either.
The second selection is the correct one:
... 4a² -20a +25 = (2a +5)²
Answer:
The sum of the first 37 terms of the arithmetic sequence is 2997.
Step-by-step explanation:
Arithmetic sequence concepts:
The general rule of an arithmetic sequence is the following:

In which d is the common diference between each term.
We can expand the general equation to find the nth term from the first, by the following equation:

The sum of the first n terms of an arithmetic sequence is given by:

In this question:

We want the sum of the first 37 terms, so we have to find 




Then

The sum of the first 37 terms of the arithmetic sequence is 2997.
Sin (a+b) = sin a. cos b + cos a. sin b
a= 50° and b=40°, then
sin(50+40) = sin 50° . cos 40° + cos 50° . sin 40°
sin(50+40) = sin 90° = 1 and
sin 50° . cos 40° + cos 50° . sin 40° = 1