The answer is A.
-3t + 7 ≥ 9
-3t + 7 - 7 ≥ 9 - 7
-3t ≥ 2
-3t /-3 ≤ 2/-3
t ≤ -2/3
If t₀ is the initial temperature of the metal then after time t hours the temperature will be t₀-5t, which must not go below -75℃.
So t₀-5t≥-75.
Answer:
Carros = 20
Motos = 30
Step-by-step explanation:
Carros = x
Motos = y
x + y = 50
4x + 2y = 140
x = 50 - y
4 (50-y) + 2y = 140 (substitución)
200 - 4y + 2y = 140
- 2y = 140 - 200
y = -60/-2
y = 30
x + 30 = 50
x = 50-30
x = 20
Answer:
The 1st Graph (A)
Step-by-step explanation:
Test by substituting values for "x":
<em>By substituting the numbers of 0</em> (0 < -3), <em>-1 </em>(-1 < -3), <em>and -2</em> (-2 < -3), <em>does that make the statement true</em>?
The answer is FALSE. None of those values are satisfactory.
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<em>Therefore, by substituting</em> <em>-4</em> (-4 < -3), <em>-5</em> (-5 < -3), <em>and -6</em> (-6 < -3), <em>these values are satisfactory and makes the statement true</em>.