No cause if I helmet cost $42 , 7 helmets will be $294.
$42 = 1 helmet
$? = 7 helmets
cross multiply = 42 × 7 = $294
Answer:


Step-by-step explanation:
<u>Given</u> :
4 cancels throughout.
<u>Solving by quadratic formula</u> :
- x = -8 ± √(8)² - 4(4)(-12) / 8
- x = -8 ± √64 + 192 / 8
- x = -8 ± √256 / 8
- x = -8 ± 16 / 8
- x = -1 ± 2
- x = 1 and x = -3
∴ Hence, the x-intercepts are (1, 0) and (-3, 0). The roots of the equation are 1 and -3.
Answer:
The solution for y is y = 2x + 1
Step-by-step explanation:
* <em>Lets explain how to solve an equation for one of the variables</em>
- We need to solve the equation 16x + 9 = 9y - 2 x for y
- That means we want to find y in terms of x and the numerical term
- the equation has two sides, one side contains x and numerical term
and the other side contains y and x
- We need to separate y in one side, and other term in the other side
* <em>Lets do that</em>
∵ 16x + 9 = 9y - 2x
- Add 2x to both sides to cancel -2x from the right side
∴ 16x + 2x + 9 = 9y - 2x + 2x
- Add like terms in each side
∴ 18x + 9 = 9y
- Divide each term by the coefficient of y ⇒ (÷9)
∴ (18 ÷ 9)x + (9 ÷ 9) = (9 ÷ 9)y
∴ 2x + 1 = y
- Switch the two sides
∴ y = 2x + 1
* The solution for y is y = 2x + 1
Answer:
Step-by-step explanation:
Let the equal number of hours be represented by variable H;
The two equations will be as follows;
Jack; 40 +30H
Mark; 50 +25H
Next, equate them;
40 + 30H = 50 + 25H
30H - 25H = 50 - 40
5H = 10
H =10/5
H = 2hrs
Therefore, they charge the same amount at 2 hrs.
B.) The amount charged;
Replace the variable H in any of the two equations above with 2 to solve for the amount.
Equation 40+30H = 40 + (30*2)
=40 + 60
= $100
Answer:
awit wala akong maintindihan. srna agad