Answer:
186
Step-by-step explanation:
if I am understanding your question correctly
Answer:
47
Step-by-step explanation:
if there are 100 total and 45 are girls, then there are 55 boys enrolled. since 8 are absent- 55-8=47
OK. These problems are easy if you know the quadratic formula,
and they're impossible if you don't.
Here's the quadratic formula:
When the equation is in the form of Ax² + Bx + C = 0
then x = [ -B plus or minus √(B²-4AC) ] / 2A
I'm sure that formula is in your text or your study notes,
right before these questions. You should cut it out or
copy it, and tape it inside the cover of your notebook.
Then, you'll always have it when you need it, until
you have it memorized and can rattle it off.
The first question says 3x² + 5x + 2 = 0
Is this in the form of Ax² + Bx + C = 0 ?
Yes ! A=3 B=5 C=2
so you can use the quadratic formula to solve it.
x = [ -B plus or minus √(B²-4AC) ] / 2A
= [ -5 plus or minus √(5² - 4·3·2) ] / 2·3
= [ -5 plus or minus √(25 - 24) ] / 6
= [ -5 plus or minus √1 ] / 6
x = -4 / 6 = -2/3
and
x = -6 / 6 = -1 .
_______________________________________
The second question says
4x² + 5x - 1 = 0
Is this in the form of Ax² + Bx + C = 0 ?
Yes it is ! A=4 B=5 C= -1
so you can use the quadratic formula to solve it.
x = [ -B plus or minus √(B²-4AC) ] / 2A
Now, you take it from here.
<u>3</u> x <u>5
</u><u />4 6
multiply the numerators (top numbers) = <u>15</u>
multiply the denominators (bottom numbers) = 24
you can reduce the fraction by dividing top and bottom of the fraction by 3
<u>15</u>÷3= <u>5</u>
24÷3= 8
Answer:she has 20 pennies because
Step-by-step explanation:80 divide by 4 = 20