$18.00 total payment
$15.00 x .05(tax) =$ .75
$15.00 x .15(tip) =$ 2.25
________________________
$ 3.00
+ $15.00
----------------------------------
$18.00
Answer:
x=0.5355 or x=-6.5355
First step is to: Isolate the constant term by adding 7 to both sides
Step-by-step explanation:
We want to solve this equation: 
On observation, the trinomial is not factorizable so we use the Completing the square method.
Step 1: Isolate the constant term by adding 7 to both sides

Step 2: Divide the equation all through by the coefficient of
which is 2.

Step 3: Divide the coefficient of x by 2, square it and add it to both sides.
Coefficient of x=6
Divided by 2=3
Square of 3=
Therefore, we have:

Step 4: Write the Left Hand side in the form 

Step 5: Take the square root of both sides and solve for x

Answer:
x=16, y=-4
Step-by-step explanation:
-1(x-y=12)
x+7y=-20
-x+y=-12
x+7y=-20
8y=-32
y=-4
x-4=12
x=16
Lines are perpendicular if the slope of one is the negative reciprocal of the other. In this case the slopes are -8/3 and 8/3, so while negative they are not reciprocal. So no, the two lines intersect but are not perpendicular.
Answer:
First term (a) =8
Common difference (d)= t2-t1
=12-8
=4
Now, sum of first 31th term (tn31) =n/2{2a+(n-1)d}
= 31/2{2×8+(31-1)4}
=31/2{16+(30×4)
=31/2(16+120)
=31/2×126
=31×63
Step-by-step explanation:
Similarly use 19 as (n) for the 19th term