Solve for r whats the answer

Mathematics

2 answers:

NARA [144]4 years ago

7 0

(9r-18)/2 < 45
9r-18< 90
9r< 108
r < 12

tankabanditka [31]4 years ago

5 0

R=12 because in order to get rid of the 2 in the denominator you have to multiply both sides by 2. Then the equation reads 9r-18<90. Next add the 18 to her 9r<108. And lastly divide by 9 to solve for r. Which in this case is 12

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solve the x:(pls help with explanation) 1. 2x/3=18 2. 1.6= x/1.5 3. 14y-8=13 4. 17+6p=9 5. x/3+1= 7/15

Darina [25.2K]

Answer:

1. X=27

2. X=2.4

3. y= 1.5

4. p=-1.33

5. X=-1.6

solution,

$1. \: \: \frac{2x}{3} = 18 \\ \: \: or \: 2x = 18 \times 3(cross \: multiplication) \\ \: \: or \: 2x = 54 \\ \: \: \: or \: x = \frac{54}{2} \\ \: \: \: x = 27$

$2. \: \: 1.6 = \frac{x}{1.5} \\ \: \: or \: x = 1.6 \times 1.5( \: cross \: multiplication) \\ \: \: \: \: x = 2.4$

$3. \: \: 14y - 8 = 13 \\ \: \: \: or \: 14y = 13 + 8 \\ \: \: or \: 14 \: y = 21 \\ \: \: or \: 14 \times y = 21 \\ \: \: \: or \: y = \frac{21}{14} \\ \: divide \: 21 \: and \: 14 \: by \: 7 \: you \: will \: get \\ \:or \: y = \frac{3}{2} \\ y = 1.5$

$4. \: \: 17 + 6p = 9 \\ \: \: or \: 6p = 9 - 17 \\ \: \: or \: 6p = - 8 \\ \: \: or \: p = \frac{ - 8}{6} \\ \: \: or \: p = \frac{ - 4}{3} \\ \: \: p = - 1.33 \\$

$5. \: \: \frac{x}{3} + 1 = \frac{7}{15} \\ \: or \: \frac{x + 1 \times 3}{3} = \frac{7}{15} \\ \: \: or \: \frac{x + 3}{3} = \frac{7}{15} \\ \: or \: 15(x + 3) = 7 \times 3( \: cross \: multiplication) \\ \: \: or \: 15x + 45 = 21 \\ \: \: or \: 15x = 21 - 45 \\ \: \: or \: 15x = - 24 \\ \: \: or \: x = \frac{ - 24}{15} \\ \: divide \: - 24 \: and \: 15 \: by \: 3 \\ \: or \: x = \frac{ - 8}{5} \\ x = - 1.6$