A square since all sides are equal and the angles aren't acute so it can't be a rhombus
Let:
x = Chemistry textbooks sold
y = Physics textbooks sold
The textbook store sold a combined total of 260, so:
The number of chemistry books sold was three times the number of physics textbooks sold, so:
Let:
Replace (2) into (1):
Replace the value of y into (2):
Answer:
Option B
Step-by-step explanation:
Option A, C and D have x- values that repeat and you cannot have that.
Y values can repeat but not x-values.
Option B has all x values with different y-values
(3a-7)^2
1. 9a^2-21a-21a+49
2. 3a(3a-7)-7(3a-7)
3. (3a-7)(3a-7)
4. Combine like terms