Find the value of the expression {ACT}

If x + 1 = 7, what is the value of x² + 2x + 1 ?
A.)  36
B.)  37
C.)  48
D.)  49
E.)  81

x + 1 = 7   {given equation}
x = 6 {subtracted 1 from each side}

x² + 2x + 1   {given expression}
= (6)² + 2(6) + 1   {substituted 6, in for x, into given expression}
= 36 + 12 + 1   {evaluated exponent and multiplied}
= 49   {added}

D.)


- Algebra House