B.
7cd, -12cd
Explanation;
Like terms have similar variables.
You have to remember P.E.M.D.A.S. when doing problems like this.
Drew used PEMDAS so we know he isn't wrong. However, Sam didn't use PEMDAS. She multiplied 2&5 instead of raising 5 to the second.
The correct answer for Sams' problem would be 30.
Hope this helps! :)
X = pencils, y = pens
8x + 6y = 8.50
4x + 4y = 5.....multiply by -2
----------------
8x + 6y = 8.50
-8x - 8y = -10 (result of multiplying by -2)
-----------------add
-2y = - 1.50
y = -1.50 / -2
y = 0.75 <=== pens cost 0.75
4x + 4y = 5
4x + 4(0.75) = 5
4x + 3 = 5
4x = 5 - 3
4x = 2
x = 2/4
x = 0.50 <== pencils cost 0.50
Answer:
1.A,B,C,D
2. AB, CD
3. AC, BD
4. Line AD (don't take my word for this one)
Step-by-step explanation:
