Question Simplify the expression 21x−4 Evaluate 21x×1−4Solution 21x−4 Show Solution Factor the expression 21(x−8) Evaluate 21x×1−4Multiply the terms 21x−4Solution 21(x−8) Show Solution Find the roots x=8 Evaluate 21x×1−4To find the roots of the expression,set the expression equal to 0 21x×1−4=0Multiply the terms 21x−4=0Move the constant to the right-hand side and change its sign 21x=0+4Removing 0 doesn't change the value,so remove it from the expression 21x=4Multiply by the reciprocal 21x×2=4×2Multiply x=4×2Solution x=8 Show Solution