Answer:
Step-by-step explanation:
Declaration
Let Heather's number of messages = x
Let Eric's number of messages = x + 9
Let Chang's number of messages = 3(x +9)
Equation
x + x + 9 + 3(x + 9) = 116
Solution
x + x + 9 + 3(x + 9) = 116 Remove the brackets
x + x + 9 + 3x + 27 = 116 Combine like terms
x + x + 3x + 9 + 27 = 116
5x + 36 = 116 Subtract 36 from both sides
5x + 36 - 36 = 116 - 36 Combine
5x = 80 Divide both sides by 5
5x/5 = 80/5
x = 16
Answer
Heather = 16
Eric = 16 + 9 = 25
Chang = 3*25 = 75
Answer:
hope this helps A chair that costs $210 was reduced by 40% for a one-day sale. After the sale, the sale price was ... SALE. tmsysWOW!$10 OFF ... off. 1.83. 169 99. Buy 1 Large Cheese Pizza for $12.50,. Get the 2nd for 1 offi ... Tai has a coupon for 20% off his total. Tax is. 8.25%. Find the total cost of Tai's purchase after the discount and tax.
Step-by-step explanation:
Answer:
The rate of change is 
ft^(2)/min
Step-by-step explanation:
The area of a circle is given by the following equation:
To solve this question, we have to realize the implicit differentiation in function of t. We have two variables, A and r. So
We have that:
.
We want to find 
So
Since the area is in square feet, the rate of change is in ft^(2)/min.
So the rate of change is ft^(2)/min
Answer:
The height of the triangle is 7cm and the base is 16cm
Step-by-step explanation:
First of all we have to know the formula to calculate area of a triangle
a = area = 56
b = base
h = heigth
a = (b * h)/2
we replace the known values and we make 2 equations
56cm² = (b * h)/2
b = h + 9cm
we replace b by (h + 9cm) in the first equation
56cm² = (h + 9cm * h)/2
56cm² * 2 = h² + 9h
0 = h² + 9h - 112cm²
we use bhaskara formula:
(-b (±) √
(b² - 4ac) ) / 2a
we replace with the known values
h = (-9 (±) √
(9² - 4*1*(-112) ) ) / 2*1
h = (-9 (±) √
(81 + 448) ) ) / 2
h = (-9 (±) √529) /2
h = (-9 (±) 23)/2
h1 = (-9 + 23) / 2
h1 = 14 / 2
h1 = 7
h2 = (-9 - 23) / 2
h2 = -32 / 2
h2 = -16
The height of the triangle is 7cm and the base is 16cm
