Let's call:
a = price of 1 apple
p = price of 1 peach

The total cost is the price of 1 apple times the number of apples plus the price of 1 peach times the number of peaches, therefore the system can be:
$\left \{ {{6a + 9p = 7.86} \atop {4a + 5p = 4.82}} \right.$

Solve for a in the second equation (you can choose to solve for any of the variables in any of the equations, try to understand what is the best):
a = (4.82 - 5p) / 4

Now, substitute in the first equation:
6 · (4.82 - 5p) / 4 + 9p = 7.86
7.23 - (15/2)p + 9p = 7.86
(3/2)p = 0.63
p = 0.42

Now, substitute this value in the formula found for a:
<span>a = (4.82 - 5·0.42) / 4</span>
= 0.68

Therefore, one apple costs 0.68$ and one peach costs 0.42$.

6 0

3 years ago

A rectangular banner has a length that is two feet shorter than twice its height, ℎ. If the expression ℎ(2ℎ−2) represents the ar

densk [106]

Answer:

h = 6

Step-by-step explanation:

Given he area of the banner expressed as;

A = ℎ(2ℎ−2)

h is the height of the banner

A is the area = 60

Substitute

60 = ℎ(2ℎ−2)

60 = 2h² - 2h

30 = h² - h

h²-h-30 = 0

Factorize;

h²-6h+5h-30 = 0

h(h-6)+5(h-6) = 0

(h-6)(h+5) = 0

h - 6 = 0 and h+5 = 0

h = 6 and -5

Since the height cannot be negative;

h = 6

Hence he height of the banner is 6

3 0

3 years ago