Step-by-step explanation:
2x - 3y - 2z = 4
[2] x + 3y + 2z = -7
[3] -4x - 4y - 2z = 10
Solve by Substitution :
// Solve equation [2] for the variable x
[2] x = -3y - 2z - 7
// Plug this in for variable x in equation [1]
[1] 2•(-3y-2z-7) - 3y - 2z = 4
[1] - 9y - 6z = 18
// Plug this in for variable x in equation [3]
[3] -4•(-3y-2z-7) - 4y - 2z = 10
[3] 8y + 6z = -18
// Solve equation [3] for the variable z
[3] 6z = -8y - 18
[3] z = -4y/3 - 3
// Plug this in for variable z in equation [1]
[1] - 9y - 6•(-4y/3-3) = 18
[1] - y = 0
// Solve equation [1] for the variable y
[1] y = 0
// By now we know this much :
x = -3y-2z-7
y = 0
z = -4y/3-3
// Use the y value to solve for z
z = -(4/3)(0)-3 = -3
// Use the y and z values to solve for x
x = -3(0)-2(-3)-7 = -1
Solution :
{x,y,z} = {-1,0,-3}
Answer:
Step-by-step explanation:
d
Answer:
This is a complete lesson with instruction & exercises for 5th grade about multiplying decimals by decimals. The interpretation for multiplying a decimal by a decimal is to think of it as taking a fractional part of a decimal number (the symbol × translates to "of"). The lesson compares multiplication by a decimal to scaling & shrinking a stick. Lastly, it shows the common shortcut to decimal multiplication (multiply as if there were no decimal points; the answer has as many decimals as the factors have in total.)
In the video below, I explain the rule for multiplying decimals (put as many decimal digits in the answer as there are in the factors.) I explain where this rule comes from, using fraction multiplication. The lesson continues below the video.
Answer:
a) 9%
, not unusual
b) 42.4%
c) 48.4%
d) 11.1%
, 44.4%
, 44.4%
Step-by-step explanation:
We have the following information from the statement:
n = 12
r = 4
a)
P (likebothofthem) = P (likefirstsong) * P (likesecondsong)
P = 4/12 * 3/11
P = 0.09 = 9%
The probability is not unusual, unusual is considered less than 0.05 or 5%
b)
P (likeneither) = P (notlikefirstsong) * P (notlikesecondsong)
P = 8/12 * 7/11
P = 0.424 = 42.4%
c) P (likeexactlyoneofthem) = P (firstsongliked) * P (secondsongnotliked) + P (firstsongnotliked) * P (secondsongliked)
P = (4/12 * 8/11) + (8/12 * 4/11)
P = 0.484 = 48.4%
d)
a)
P (likebothofthem) = P (likefirstsong) * P (likesecondsong)
P = 4/12 * 4/12
P = 0.111 = 11.1%
The probability is not unusual, unusual is considered less than 0.05 or 5%
b)
P (likeneither) = P (notlikefirstsong) * P (notlikesecondsong)
P = 8/12 * 8/12
P = 0.444 = 44.4%
c) P (likeexactlyoneofthem) = P (firstsongliked) * P (secondsongnotliked) + P (firstsongnotliked) * P (secondsongliked)
P = (4/12 * 8/12) + (8/12 * 4/12)
P = 0.444 = 44.4%
