Which of the following points are solutions to the inequality below?

PLEASE ANSWER !

ivanzaharov [21]

Answer:I think no, because 25+35+45=150. 150x3=450

Maybe, for 4 months he'd have enough. So, 150x4=600. So Jamal would have some extra money!

Step-by-step explanation:

8 0

2 years ago

A scientist estimated that a mixture would need 6 milliliters of a chemical to balance. The actual amount needed was 7 millilite

Mashcka [7]

Percent relative error is calculated by the formula: (experimental value - literature value/ experimental value) x 100%

Therefore, (6-7/7) x 100% = 14.3%
Your answer is in absolute value :)

6 0

2 years ago

What are the roots of the equatio<br> x² - x -42=0

Alex17521 [72]

$x^2-x-42=0\\x^2+6x-7x-42=0\\x(x+6)-7(x+6)=0\\(x-7)(x+6)=0\\x=7 \vee x=-6$

4 0

1 year ago

Read 2 more answers

Kay scored above 90% on five of her math quizzes, 80% to 90% on fourteen of them, and 70% to 80% on two of them. What is the exp

Leya [2.2K]

In total, Kay took 5+14+2=21exams. she got 80%-90% on 14 of them. the probably is 14/21 which is 2/3. Therefore, the probability of Kay getting 80%-90% on her next exam is 2/3 or 66.6%

3 0

2 years ago

Topic: The Quadratic Formula

Finger [1]

Answer:

Step-by-step explanation:

The quadratic formula for a equation of form

ax²+bx + c = 0 is

$x= \frac{-b +- \sqrt{b^2-4ac} }{2a}$

For the first equation,

x²+3x-4=0,

we can match that up with the form

ax²+bx + c = 0

to get that

ax² = x²

divide both sides by x²

a=1

3x = bx

divide both sides by x

3 = b

-4 = c

. We can match this up because no constant multiplied by x could equal x² and no constant multiplied by another constant could equal x, so corresponding terms must match up.

Plugging our values into the equation, we get

$x= \frac{-3 +- \sqrt{3^2-4(1)(-4)} }{2(1)} \\= \frac{-3+-\sqrt{25} }{2} \\ = \frac{-3+-5}{2} \\= -8/2 or 2/2\\= -4 or 1$

as our possible solutions

Plugging our values back into the equation, x²+3x-4=0, we see that both f(-4) and f(1) are equal to 0. Therefore, this has 2 real solutions.

Next, we have

x²+3x+4=0

Matching coefficients up, we can see that a = 1, b=3, and c=4. The quadratic equation is thus

$x= \frac{-3 +- \sqrt{3^2-4(1)(4)} }{2(1)}\\= \frac{-3 +- \sqrt{9-16} }{2}\\= \frac{-3 +- \sqrt{-7} }{2}\\$

Because √-7 is not a real number, this has no real solutions. However,

(-3 + √-7)/2 and (-3 - √-7)/2 are both possible complex solutions, so this has two complex solutions

Finally, for

4x² + 1= 4x,

we can start by subtracting 4x from both sides to maintain the desired form, resulting in

4x²-4x+1=0

Then, a=4, b=-4, and c=1, making our equation

$x=\frac{-(-4) +- \sqrt{(-4)^2-4(4)(1)} }{2(4)} \\= \frac{4+-\sqrt{16-16} }{8} \\= \frac{4+-0}{8} \\= 1/2$

Plugging 1/2 into 4x²+1=4x, this works as the only solution. This equation has one real solution

7 0

2 years ago