Algebra

Taking the square root of both sides of the equation x^2 = 49 yields both positive and negative solutions, giving x = 7 and x = -7. Option A is incomplete because it forgets that squaring a negative number also produces a positive result. Option D is incorrect because it simply divides 49 by 2.

Option C is correct because subtracting 3 from both sides of the equation yields 5x = 25, and dividing by 5 gives x = 5. Option B is incorrect because substituting 4 for x results in 23, not 28. Option D is incorrect because it overestimates the value, resulting in 33.

Option C is correct because subtracting 3 from both sides of the equation yields 5x = 25, and dividing by 5 gives x = 5. A diagram for this topic isn't available yet — the worked example below walks the same reasoning step by step.

• !Option B is incorrect because substituting 4 for x results in 23, not 28.
• !Option B is incorrect because substituting 10 for x results in 18, not 21, which fails to satisfy the equation.
• !Option B is incorrect because it multiplies the exponents instead of adding them, while option A incorrectly adds the coefficients.
• !Option D is incorrect because it simply divides 49 by 2.
• !Option A is incorrect because it results from a sign error where -2(-3) is mistakenly calculated as -6 instead of +6.

Answer each from memory — you'll see instantly whether you're right and why.

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