7/10 - 1/4 use common denominators
28/40 - 10/40 = 18/40 = 9/20
18/1
36/2
72/4
...and many more....
the answer would be 10 because you have to times by 2.5 on both sides to get t on its own.
4 × 2.5 is 10
Answer:
not
Step-by-step explanation:
![\left[\begin{array}{ccc}-2&4\\1&3\end{array}\right] *\left[\begin{array}{ccc}-2&1\\3&7\end{array}\right]=](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%264%5C%5C1%263%5Cend%7Barray%7D%5Cright%5D%20%2A%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%261%5C%5C3%267%5Cend%7Barray%7D%5Cright%5D%3D)
First is A and Second is B
Let's find A*B
![\left[\begin{array}{ccc}-2(-2)+4*3&-2*1+4*7\\1(-2)+3*3&1*1+3*7\end{array}\right] =\left[\begin{array}{ccc}16&26\\7&22\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%28-2%29%2B4%2A3%26-2%2A1%2B4%2A7%5C%5C1%28-2%29%2B3%2A3%261%2A1%2B3%2A7%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D16%2626%5C%5C7%2622%5Cend%7Barray%7D%5Cright%5D)
b)
![\left[\begin{array}{ccc}-2&1\\3&7\end{array}\right] \left[\begin{array}{ccc}-2&4\\1&3\end{array}\right] =](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%261%5C%5C3%267%5Cend%7Barray%7D%5Cright%5D%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%264%5C%5C1%263%5Cend%7Barray%7D%5Cright%5D%20%3D)
Now let's find B*A
![\left[\begin{array}{ccc}-2(-2)+1*1&-2*4+1*3\\3(-2)+7*1&3*4+7*3\end{array}\right] =\left[\begin{array}{ccc}5&-5\\1&23\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%28-2%29%2B1%2A1%26-2%2A4%2B1%2A3%5C%5C3%28-2%29%2B7%2A1%263%2A4%2B7%2A3%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%26-5%5C%5C1%2623%5Cend%7Barray%7D%5Cright%5D)
c) They are not
Answer:
(5, 9)
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtract Property of Equality
<u>Algebra I</u>
- Solving systems of equations using substitution/elimination
Step-by-step explanation:
<u>Step 1: Define Systems</u>
x - 5y = -40
18x - 5y = 45
<u>Step 2: Rewrite Systems</u>
18x - 5y = 45
- Multiply both sides by -1: -18x + 5y = -45
<u>Step 3: Redefine Systems</u>
x - 5y = -40
-18x + 5y = -45
<u>Step 4: Solve for </u><em><u>x</u></em>
<em>Elimination</em>
- Combine equations: -17x = -85
- Divide -17 on both sides: x = 5
<u>Step 5: Solve for </u><em><u>y</u></em>
- Define equation: x - 5y = -40
- Substitute in <em>x</em>: 5 - 5y = -40
- Isolate <em>y</em> term: -5y = -45
- Isolate <em>y</em>: y = 9
