A Regression Analysis (Involving 45 Observations) Relating a Dependent Variable $\widehat { y }$

Essay

A regression analysis (involving 45 observations) relating a dependent variable (y) and two independent variables resulted in the following information.
​ $\widehat { y }$ = 0.408 + 1.3387x₁ + 2x₂
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The SSE for the above model is 49.
When two other independent variables were added to the model, the following information was provided.
​ $\widehat { y }$ = 1.2 + 3.0x₁ + 12x₂ + 4.0x₃ + 8x₄
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This latter model's SSE is 40.
At a 5% significance level, test to determine if the two added independent variables contribute significantly to the model.