Answer:
-3
Step-by-step explanation:
Since x=1, we can simplify the equation to 9+7y=-12.
To find the value of 7y, we first have to find what is missing.
-12-9=-21, so 7y has to be equal to -21. -21/7 equals -3, so y=-3.
Answer:
(8,-9)
Step-by-step explanation:
using the principle of vectors, you match each number to their coordinates and add them
so we have (7+1,-12+3)
which is equal to (8,-9)
The process is similar to (and easier* than) adding three 4-digit numbers. Add the numbers in each column.
The sum is ...
(2+1-3)x³ +(-4+6+2)x² +(6-8-4)x +(-3+12-7)
= 0x³ +4x² -6x +2
The sum is 4x² -6x +2
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* The process is easier because there are no "carry" operations from one column to another as there may be when adding multi-digit numbers.