Q. Four times a number decreased by 4 is between −40 and 88.Find the interval for valid values. (The answer should be in interval notation.)
Define Unknown Number: Let's denote the unknown number as 'x'. The problem states that four times a number decreased by four is between −40 and 88. We can write this as an inequality:−40<4x−4<88
Solve Left Inequality: First, we will solve the left part of the inequality:−40<4x−4We need to isolate the variable x, so we will add 4 to both sides of the inequality:−40+4<4x−4+4−36<4x
Isolate Variable 'x': Now, we divide both sides of the inequality by 4 to solve for 'x':−36÷4<4x÷4−9<x
Solve Right Inequality: Next, we will solve the right part of the inequality:4x−4<88Again, we will add 4 to both sides of the inequality:4x−4+4<88+44x<92
Combine Inequalities: We divide both sides of this inequality by 4 to solve for 'x':4x÷4<92÷4x<23
Combine Inequalities: We divide both sides of this inequality by 4 to solve for 'x':4x÷4<92÷4x<23Now we combine the two inequalities to find the interval for 'x':−9<x<23This is the interval notation for the valid values of 'x'.
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