Heart Block Practice Quiz

Subtract 5 from both sides to get 2x = 8, then divide by 2 to obtain x = 4. This problem demonstrates basic algebraic solving techniques.

The area is calculated by multiplying length by width, which gives 8 * 3 = 24. This is a basic application of the area formula for rectangles.

15% of 200 is found by multiplying 200 by 0.15, which equals 30. This problem practices converting percentages to decimals and performing multiplication.

The sum of the set is 24 and dividing by the number of values (4) gives a mean of 6. This question reinforces the concept of calculating the average.

Divide both the numerator and denominator by their greatest common divisor, which is 4, simplifying 8/12 to 2/3. Recognizing common factors is essential for reducing fractions.

Subtracting 2x from both sides yields x - 4 = 1, and then adding 4 gives x = 5. This equation is solved by isolating the variable on one side.

Factoring the quadratic gives (x - 2)(x - 3) = 0, leading to the solutions x = 2 and x = 3. This demonstrates how factorization can be used to solve quadratic equations.

The slope is calculated by the change in y over the change in x: (11 - 3)/(6 - 2) = 8/4 = 2. This reflects the rate of change between the two points.

Substitute x = 3 into the function: 2(3²) - 3(3) + 1 equals 18 - 9 + 1, which simplifies to 10. This shows proper evaluation of a quadratic function.

The probability of drawing a blue marble is the number of blue marbles over the total number of marbles: 3/(5+3) = 3/8. This problem demonstrates a basic probability calculation.

The increase is 14, and when divided by the original score of 70, then multiplied by 100 gives a 20% increase. This problem reinforces how to calculate percentage change.

In a 30-60-90 right triangle, the side opposite the 30° angle is half the length of the hypotenuse. Thus, the side length is 10/2 = 5.

Using the formula C = 2πr, solve for r: r = 31.4/(2*3.14) = 31.4/6.28, which gives 5. This is an application of the circle circumference formula.

Distance is calculated by multiplying speed by time. Here, 60 km/h multiplied by 2.5 hours equals 150 km.

Dividing $225 by the hourly rate of $15 gives the number of hours needed: 225/15 = 15 hours. This problem illustrates the relationship between work time and earnings.

By rewriting the second equation as x = y + 1 and substituting into the first equation, we get 2(y + 1) + y = 10, which simplifies to 3y = 8, so y = 8/3 and x = 11/3. This method employs substitution to solve systems of linear equations.

The function is in vertex form, f(x) = (x - h)² + k, where the vertex is located at (h, k). Here h = 2 and k = 3, so the vertex is (2, 3).

Since 50 can be factored into 25 × 2, the square root of 50 is √25 × √2, which simplifies to 5√2. This simplification is a basic exercise in extracting perfect square factors.

Differentiating term by term: the derivative of 3x² is 6x, the derivative of -4x is -4, and the constant 5 has a derivative of 0. Thus, the derivative is 6x - 4, applying the power rule.

Since order matters and no letter is repeated, the number of possible codes is given by the permutation formula P(4, 3) = 4 × 3 × 2 = 24. This problem applies basic principles of permutations in combinatorics.