Big ! +brainliest ! !

in a test, all questions were of equal value. if you answered 9 of the first 10 questions correctly, but only 3/10 of the remaining questions correctly, you would have scored 50% for the whole test. find the number of questions in the test.
use an algebraic equation!

Step-by-step explanation:

We will set up an algebraic equation by counting the wrong answers.

Final score is 50% so half of the answers are wrong.

Let the number of question be x

x/2 answers are wrong.

There is 1 wrong answer in the first 10 questions.

Out of the (x-10) questions remaining, 3/10 are correct so 7/10 of them are wrong.

Adding them together, 1+7/10(x-10)=x/2

1+7/10x-7 = x/2

1/5x = 6

x = 30

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.