Which statement must be true

Using the quadratic formula to solve 2x^2 = 4x – 7, what are the values of x?

Colt1911 [192]

Answer:

Step-by-step explanation:

To use the quadratic formula, we must write the quadratic in standard form, viz:

2x^2 - 4x + 7 = 0

Start by calculating the discriminant. That's b^2 - 4(a)(c). Here,

a = 2, b = -4 and c = 7, and so the discriminant for this particular problem is

(-4)^2 - 4(2)(7), or 16 - 56, or 40.

Recall that a positive discriminant indicates two real, unequal roots.

Now we write out the whole quadratic formula, with the appropriate constants inserted (see above):

-(-4) ± √40 4 ± (√4)(√10) 4 ± 2√10

x = --------------------- = ---------------------- = ---------------

2(2) 4 4

2 ± √10

which reduces to x = --------------

2

6 0

3 years ago

In a certain university admissions department, 70 more males than females submitted applications for admissions. 20% of the fema

Anuta_ua [19.1K]

Answer:

In total, 1130 people applied in the University.

Step-by-step explanation:

Total applicants admitted = 256

Let the number of females who applied in University = k

So, the number of males who applied = ( k + 70)

Now, 20 %of females are admitted ⇒ 20% of (k) is admitted

or, the number of females admitted in university = $\frac{20}{100} \times k = 0.2k$

Also , 25 %of males are admitted ⇒ 25% of (k + 70) is admitted

or, the number of males admitted in university = $\frac{25}{100} \times (k+70) = 0.25(k+70)$

So, according to the question:

0.20k + 0.25(k+70) = Total admissions = 256

or, 0.2k + 0.25k + 17.5 = 256

⇒0.45k = 238.5

or, k = 238.5/0.45 = 530

Hence, total number of females who applied = 530

And Total males who applies = ( k + 70) = 600

Now, TOTAL Applications = MALE applications + FEMALE applications

= 530 + 600 = 1130

Hence, in total 1130 people applied in the University.

4 0

3 years ago

Which lengths could be the sides LKM of the triangle, respectively?

Tanya [424]

Answer:B

Step-by-step explanation:

Using what is known as the "Triangle Inequality Theorem" a+b can not be less than c or else it is not a triangle. (A and B are the smallest sides of the triangle).

A) 6cm + 15cm = 21cm which is less than 23cm: Not a triangle

B) 5cm + 9cm = 14cm which is greater than 13cm: This makes a triangle and therefore the answer is B

C) 5cm + 8cm = 13cm which is less than 13cm: Not a triangle

6 0

3 years ago

Read 2 more answers

Triangle STU ~ triangle, the triangles are similar by

Karolina [17]

Answer:

d

Step-by-step explanation:

cause

4 0

3 years ago

2.) Helene, who drives a cab, is paid $250 per week. She averages $75 per day in tips.

salantis [7]

Answer:

she earns $375

Step-by-step explanation:

well you would do 75 x 5 then you get 375

7 0

4 years ago