Answer:
see explanation
Step-by-step explanation:
Given
2x² + x - 1 = 2 ( subtract 2 from both sides )
2x² + x - 3 = 0
Consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term
product = 2 × - 3 = - 6 and sum = + 1
The factors are - 2 and + 3
Use these factors to split the x- term
2x² - 2x + 3x - 3 = 0 ( factor the first/second and third/fourth terms )
2x(x - 1) + 3(x - 1) = 0 ← factor out (x - 1) from each term
(x - 1)(2x + 3) = 0
Equate each factor to zero and solve for x
x - 1 = 0 ⇒ x = 1
2x + 3 = 0 ⇒ 2x = - 3 ⇒ x = - 
Answer:
-4
Step-by-step explanation:
-4/3÷2/-6
⇒ -4/3×-6/2
⇒ -24/6
⇒ -4
Answer:
29° ; 61°
Step-by-step explanation:
Let one angle = x°
Other angle = (x + 32)°
x + x + 32 = 90 {given they are complementary}
2x + 32 = 90
2x = 90 -32
2x = 58
x = 58/2
x = 29
One angle = 29°
Other angle = 29 + 32 = 61°
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
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