Answer:
see explanation
Step-by-step explanation:
Her error is in squaring (2y)²
She has (2y)² = 2y²
when it should be 2y × 2y = 4y²
Then
(2y)² = 6² + 8²
4y² = 36 + 64
4y² = 100 ( divide both sides by 4 )
y² = 25 ( take square root of both sides )
y = 
= 5
Answer:
y = -1/4x
Step-by-step explanation:
16y = -4x
y = -1/4x
Answer:
(7/8 - 4/5)^2 = 9/
1600
= 0.005625
Step-by-step explanation:
Subtract: 7/
8
- 4/
5
= 7 · 5/
8 · 5
- 4 · 8/
5 · 8
= 35/
40
- 32/
40
= 35 - 32/
40
= 3/
40
For adding, subtracting, and comparing fractions, it is suitable to adjust both fractions to a common (equal, identical) denominator. The common denominator you can calculate as the least common multiple of both denominators - LCM(8, 5) = 40. In practice, it is enough to find the common denominator (not necessarily the lowest) by multiplying the denominators: 8 × 5 = 40. In the next intermediate step, the fraction result cannot be further simplified by canceling.
In words - seven eighths minus four-fifths = three fortieths.
Exponentiation: the result of step No. 1 ^ 2 = 3/
40
^ 2 = 32/
402
= 9/
1600
In words - three-fortieths squared = nine one-thousand six-hundredths.
