The first given equation is:
x - 7y = -20
We can rewrite this equation as follows:
x = 7y - 20 ...........> equation I
The second given equation is:
-3x + 9y = 36 ..........> equation II
Substitute with equation I in equation II to get the value of the y as follows:
-3x + 9y = 36
-3(7y-20) + 9y = 36
-21y + 60 + 9y = 36
-12y = 36-60 = -24
y = (-24) / (-12) = 2
Now use the value of the y and substitute in equation I to get the value of the x as follows:
x = 7y - 20
x = 7(2) - 20 = 14 - 20 = -6
Based on the above calculations:
x = -6
y = 2
Answer:
This is an indirectly proportional relation, because the food will last less if the number of animals increases.
What we can do is a rule of three, as we know that the food lasts 30 days for 100 animals, and we want to know how many days does it last for 120:
30 days -- 100 cows
x days -- 120 cows
As it's an inderect rule of three, x = = 25.
The food will last 25 days for them.
Arc secant is not equal to cosine. It can be confusing, because the "-1" exponent (which is used to denote arc secant), could also mean the inverse function of secant. Yes, the inverse function of secant would be cosine. Therefore, the inverse of the inverse of cosine, is simply cosine itself.
Answer:
x + 25.75 ≥ 53.88
She needs to earn $28.13 more to buy the headphones.
Step-by-step explanation:
Hi, to answer this question we have to add the amount of money saved by Tania (25) and the amount of money she needs to earn (x). That expression must be higher or equal to the price of the headphones (53.88)
Mathematically speaking
x + 25.75 ≥ 53.88
Solving:
x ≥ 53.88 -25.75
x ≥ 28.13
She needs to earn $28.13 more to buy the headphones.
Feel free to ask for more if needed or if you did not understand something.