Answer:
41/12
Step-by-step explanation:
{2x + 3y = 18
x + 7y = 31}
2x+ 3y = 18
x=31-7
2(31-7)+3y=18
y=4
x=31-7*4
x=3
(x,y) = (3,4)
simple interest:
principal x ( 1 + (rate as decimal x number of years))
example if you put 100 dollars in a bank for 5 years at 5% interest at the end of the 5 years you would have:
100 x (1+(0.05 x 5)) = 100 x (1+(0.25)) = 100 x 1.25 = 125 dollars
125-100 = 25 dollars interest
Answer:
Instrumental understanding – having a mathematical rule and being able to apply and manipulate it. Relational understanding – having a mathematical rule, knowing how to use it AND knowing why it works.
Step-by-step explanation:
Instrumental understanding involves “memorising which problems a method works for and which not, and also learning a different method for each new class of problems” (Skemp 1987, p. 159), is a desire to know “some kind of rule for getting the answer” (p. 155) so that a student can “latch on it and ignore the rest”
Hope this helps but I think the answer is $8.91.
