ACT Practice Test 2024
Factoring Perfect Squares
(a + b)2 = a2 + 2ab + b2.
midpoint formula
(x₁+x₂)/2, (y₁+y₂)/2
double decrease
A $100 dress was marked down 50% in March then that price was marked down 25% in April. What is the price of the dress?
What is a geometric sequence?
A Geometric Sequence is a sequence of numbers that increases or decreases by multiplying or dividing by the same amount every time. Ex: 2, 6, 18, 54, 162... A question on the test would ask "what is the 7th term in the sequence above?" It would be 1,458 because the common difference is a multiple of 3.
What is a parallelogram
A closed four-sided figure in which the opposite sides are parallel.
Scientific Notation
A method of writing or displaying numbers in terms of a decimal number between 1 and 10 multiplied by a power of 10.
What is a trapezoid?
A quadrilateral with exactly one pair of parallel sides
What is an isosceles triangle?
A triangle with two equal angles and two equal length sides.
Area of a circle
A=πr²
What is an arithmetic sequence?
An Arithmetic Sequence is a sequence of numbers that increase or decreases by adding or subtracting the same amount every time. Ex: 2,5,8,11,14,17... A question on the test would ask "what is the 7th term in the sequence above?" It would be 20 because every number has a difference of 3.
factoring perfect cubes
Formula: a3 + b3 = (a + b)(a2 - ab + b2)
double increase
If the average price of a car increases 5% each year, and the average price in 2020 was 40,000 what will the average price be in 2022?
What does PEMDAS mean?
Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction
what is absolute value?
The distance a number is from zero on a number line
What is Absolute Value?
The distance a number is from zero. It is always positive
What is a rhombus?
a parallelogram with 4 congruent sides
Distance Formula
d = √[( x₂ - x₁)² + (y₂ - y₁)²]
slope formula
m=(y 2—y 1)/(x 2—x 1).
What is a least common multiple
of two numbers is the smallest number that both numbers factor into evenly. Example- The first five multiples of of 4 are {4, 8, 12, 16, 20} making the least common multiple of 3 and 4 equal to 12.
Quadratic Formula
x = -b ± √(b² - 4ac)/2a
y-intercept formula
y=mx+b
