Answer:
25
Step-by-step explanation:
You have is circled plus 25 is 5 and 5 multiplied and 5 is a prime number.
B; 25.65+13.23+6.35=45.23
To do this mentally just add the 2 decimals places together first (1.23). Then just add the whole numbers (44). Then add the 2 numbers together, 44+1.23=45.23
2x + y = 5
x − 2y = 10
y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10
<em>add 10 to each side</em>
<em>5x-10+10 = 10 + 10</em>
<em>5x=20</em>
5x = 0 <em>this is the error</em>
He needs to add 10 to each side
