The first thing you want to do is plug in x and y into both equations:
a(3) + b(4) = 4
b(3) + a(4) = 8
rearrange to line up a’s and b’s
3a + 4b = 4
4a + 3b = 8
now you want to choose a or b and multiply each equation by a number to make them have the same amount of a’s or b’s.
4(3a + 4b = 4) = 12a + 16b = 16
3(4a + 3b = 8) = 12a + 9b = 24
Now we subtract the bottom equation from the top and solve for b:
12a + 16b - (12a + 9b) = 16 - 24
7b = -8
b = -8/7
Now we plug back in for b to one of the original equations:
3a + 4(-8/7) = 4
3a + (-32/7) = 4
3a - (32/7) = 4
3a = 4 + (32/7)
3a = (28/7) + (32/7)
3a = 60/7
a = (60/7)/3 = 20/7.
Finally, plug a and b in together to double check using the second equation.
4a + 3b = 8
4(20/7) + 3(-8/7) = ?
(80/7) - (24/7) = ?
56/7 = 8.
Answer:
for number 1, you plug -3 in for x in the equation. and for number 2, you plug in 2 for y in the equation. you do this to find the missing values of the variables.
1. y= -10
2. x= -1
Step-by-step explanation:
i hope this helps :)
Twenty four millimeters of oil
We are given with the expression <span>tan2x / x</span> and asked to evaluate the expression to limit as theta approaches zero. In this case, we substitute first zero. The answer is zero over zero. This is indeterminate so we derive the terms accdg to L'hopital's rule. The derivative is 2 sec^2 2x/1. cos 2x is 1 so is sec^2 2x. Hence the answer is 2.
Answer:
$27.31 (rounded to the nearest cent)
