We want to find the values of a, b, c, and d such that the given matrix product is equal to a 2x2 identity matrix. We will solve a system of equations to find:
<h3>
Presenting the equation:</h3>
Basically, we want to solve:
![\left[\begin{array}{cc}-1&2\\a&1\end{array}\right]*\left[\begin{array}{cc}b&c\\1&d\end{array}\right] = \left[\begin{array}{cc}1&0\\0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%262%5C%5Ca%261%5Cend%7Barray%7D%5Cright%5D%2A%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Db%26c%5C%5C1%26d%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%260%5C%5C0%261%5Cend%7Barray%7D%5Cright%5D)
The matrix product will be:
![\left[\begin{array}{cc}-b + 2&-c + 2d\\a*b + 1&a*c + d\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-b%20%2B%202%26-c%20%2B%202d%5C%5Ca%2Ab%20%2B%201%26a%2Ac%20%2B%20d%5Cend%7Barray%7D%5Cright%5D)
Then we must have:
-b + 2 = 1
This means that:
b = 2 - 1 = 1
We also need to have:
a*b + 1 = 0
we know the value of b, so we just have:
a*1 + b = 0
Now the two remaining equations are:
-c + 2d = 0
a*c + d = 1
Replacing the value of a we get:
-c + 2d = 0
-c + d = 1
Isolating c in the first equation we get:
c = 2d
Replacing that in the other equation we get:
-(2d) + d = 1
-d = 1
Then:
c = 2d = 2*(-1) = -2
So the values are:
If you want to learn more about systems of equations, you can read:
brainly.com/question/13729904
6,635 should be standard form
Answer:
16
Step-by-step explanation:
Let the 1st part of your answer be x
, so the 2nd part will be 40-x
. From the given information, we can write the equation: (1/4)x = (3/8) × (40-x)
. We can simplify this into (1/4)x = (120-3x)/8
; 8x = 480-12x
; 8x+12x = 480
; 20x = 480
; x = 480/20; x = 24
Therefore, the 1st part = 24
Plug this into your 40-x equation to get: 40 - 24 = 16
Answer:
(-2, -4.5)
Step-by-step explanation:
We can solve this equation with substitution.
x=2y+7
3x-2y=3
We can "substitute" 2y+7 for x into the second equation:
3(2y+7)-2y=3
Distribute the 3
6y+21-2y=3
Add like terms
4y+21=3
Subtract 21 from both sides
4y=-18
Divide both sides by 4 to isolate y
y=-4.5
Plug -4.5 back in for y:
x=2(-4.5)+7
x=-9+7
x=-2
(x,y)=(-2,-4.5)
If a=0, then the denominator is equal to 0. Since you cannot divide by zero, you are not allowed to do this.
Hope This helps!