5a - (-2a) + 9
When you subtract a negative number, you can replace the 'double negative' with a positive, or addition. So, instead of subtracting -2a, you can add 2a.
5a + 2a + 9 Combine like-terms
7a + 9
Answer:
25
Step-by-step explanation:
20% of 25 is 5
Answer:
±2/11
Step-by-step explanation:
Take the square root of both sides of the equation:
![\sqrt{x^2}=\sqrt{\dfrac{4}{121}}\\\\\boxed{x=\pm\dfrac{2}{11}}](https://tex.z-dn.net/?f=%5Csqrt%7Bx%5E2%7D%3D%5Csqrt%7B%5Cdfrac%7B4%7D%7B121%7D%7D%5C%5C%5C%5C%5Cboxed%7Bx%3D%5Cpm%5Cdfrac%7B2%7D%7B11%7D%7D)
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Here, we need to recognize that (-2/11)^2 = (2/11)^2 = 4/121, so both the positive and negative roots of 4/121 are solutions to the equation.
9 is your answer. When you have a negative squared number, your answer will be positive. Think of it like -3*-3.