Answer:
The final answers are x = 1 OR x = -3.
Step-by-step explanation:
Given the equation is x^2 -3 = -2x
Rewriting it in quadratic form as:- x^2 +2x -3 = 0.
a = 1, b = 2, c = -3.
Using Quadratic formula as follows:- x = ( -b ± √(b² -4ac) ) / (2a)
x = ( -2 ± √(4 -4*1*-3) ) / (2*1)
x = ( -2 ± √(4 +12) ) / (2)
x = ( -2 ± √(16) ) / (2)
x = ( -2 ± 4 ) / (2)
x = (-2+4) / (2) OR x = (-2-4) / (2)
x = 2/2 OR x = -6/2
x = 1 OR x = -3
Hence, final answers are x = 1 OR x = -3.
Answer:
x=3 y=11
Step-by-step explanation:
2x+3=9
2x=6
x=3
y-4=7
y=11
We know that
At sea level, the height is 0 and
the pressure is 98 kilopascals
At 1000 ft, the height is 1000 and
the pressure <span>decreases about 11.41%
</span>i(100%-11.41%)/100----> (0.8859)
therefore
1) at 1000 ft--------> the pressure is 98*(0.8859)----------> 86.82 kilopascals
2) at 2000 ft--------> the pressure is 86.82*(0.8859)-------> 76.91 kilopascals
3) at 3000 ft--------> the pressure is 76.91*(0.8859)-------> 68.14 kilopascals
4) at 4000 ft---------> the pressure is 68.14*(0.8859)-------> 60.36 kilopascals
the answer is
<span>The pressure at an altitude of 4000 m is about </span>60.36 kilopascals
First, let's cancel out the x by multiplying 2x + 18y = -9 by -2.
-2 ( 2x + 18y = -9) = -4x -36y = 18
Then, we combine the two equations.
-4x + 4x = 0
18y - 36y = -18y
-27 + 18 = -9
Our new equation is -18y = -9.
Now, divide both sides by -18.
-18y / -18 = y
-9/ -18 = 1/2
y = 1/2
We can plug in a value for y since y = 1/2 now.
Let's use 2x + 18y = -9
Plug in y.
2x + 18(1/2) = -9
2x + 9 = -9
Then, subtract 9 from both sides.
2x = -18
Divide by 2.
2x/2 = x
-18/2 = -9
x = -9
Lastly, we can plug in both x and y values to see it works.
2(-9) + 18(1/2) = -9
-18 + 9 = -9
Therefore, the values of x and y does work.
x = -9
y = 1/2
<em>Total number of coin that George has
16 + 28 + 32 + 4 = 80 coins
total number of coins sold by George
= 15% of 80
= 15/100 X 80
= 12 coins (ans)</em>
