Answer:
length is 78
Step-by-step explanation:
Perimeter of rectangle is P = 2 (l +w)
278 = 2(l + 61)
l = 78
This has a slope of 3, you can plot it on a graph and count rise over run.
Answer:
Sue must score 94 on the final test to earn a B.
Step-by-step explanation:
There are five tests in total.
Sue's average on the first four tests is 84.
If after the final test, she scores X, she will have a B on average of five tests.
We have the following equation:
86 = (4 × 84 + X)/5
<=> X = 5 × 86 - 4 × 84
=> X = 94
Answer:
x = 0
y = -2
Step-by-step explanation:
-5x + y = -2
x = 0
y = -2
-3x + 6y = -12
x = 0
y = -2
Answer:
3 + 4 = 7 which is true.
Step-by-step explanation:
Whenever you have an equation with a plain variable (that is, no exponent included), there is only one number that will work when substituted for x.
To solve it, you have to "undo" what is done to the variable. You also go in the reverse order of operations, so you do the addition/subtract first, then multiplication/division.
You also have to do the same to both sides, kind of like keeping a balance scale in balance.
In this case, we subtract 4 from both sides first:
3x + 4 -4 = 7 - 4
The + 4 - 4 cancel each other out, so you get:
3x = 3
3x means "3 times x" so you divide by 3 to undo it. I will use the / to indicate division:
3x / 3 = 3 /3
so 1x = 1.
Since 1x is "1 times x" it is the same as x by itself, so:
x=1
AND, if we substitute 1 back into the original equation (the asterisk stands for multiply):
3 * 1 + 4 = 7
3 * 1 is 3, so:
3 + 4 = 7 which is true.
1 is the only number that works.
Hope this helped.
