Suppose you take an 80 question mc test with 5 choices if 60% is passing, what are your chances of passing

Which equation represents the relationship 3 less than a number is -6

Phantasy [73]

X-3=-6
if you take away 3 from a number, you will get -6
x=-3

5 0

3 years ago

Determine whether the set is well defined. The set of people who wear expensive perfume.

Tanya [424]

Yes, the set of people who wear expensive perfume is well-defined. A set is said to be well-defined if its definition assigns it a unique value. Otherwise, the set is said to be not well-defined or ambiguous."Well-defined” means that any given object in the entire world, whether abstract or concrete is either an element of the set or isn't.

3 0

3 years ago

<img src="https://tex.z-dn.net/?f=%5Cleft%20%5C%7B%20%7B%7Ba%5E2%20-2a-b%5E2%3D0%7D%20%5Catop%20%7B2b%2B2ab%3D0%7D%7D%20%5Cright

oksian1 [2.3K]

Given :-

a² - 2a - b² = 0
2b + 2ab = 0

To find :-

Value of a and b .

Solution :-

Taking second equation:-

2b + 2ab = 0
2b ( 1 + a ) = 0
2b = 0 or (1+a) = 0
b = 0 , a = -1

Substitute in first equation :-

a² - 2a - b² = 0

When b = 0 ,

a² - 2a - 0² = 0
a² - a = 0
a( a -1) =0
a = 0 , 1

When a = -1 ,

(-1)² - 2*(-1) - b² = 0
1 + 2 - b² = 0
b² = 3
b = ±√3

Answer :-

a = 0,1 ; b = 0
a = -1 , b = ±√3

8 0

2 years ago

I dont really know how to do soh cah toah. please help me find x.

Ipatiy [6.2K]

First notice that the triangle with sides $x,y,a$ and the triangle with sides $z,a+b,x$ are similar. This is true because the angle between sides $x,y$ in the smaller triangle is clearly $30^\circ$ , while the angle between sides $y,z$ in the larger triangle is clearly $60^\circ$ . So the triangles are similar with sides $x,y,a$ corresponding to $a+b,z,x$ , respectively.

Now both triangles are $30^\circ-60^\circ-90^\circ$ , which means there's a convenient ratio between its sides. If the length of the shortest leg is $\ell_1$ , then the length of the longer leg is $\ell_2=\sqrt3\ell_1$ and the hypotenuse has length $\ell_3=\sqrt{{\ell_1}^2+{\ell_2}^2}=2\ell_1$ .

Since $x$ is the shortest leg in the larger triangle, it follows that $a+b=2x$ , so $a+b=15=2x\implies x=\dfrac{15}2$